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1 HXCOMM Use DEFHEADING() to define headings in both help text and texi
2 HXCOMM Text between STEXI and ETEXI are copied to texi version and
3 HXCOMM discarded from C version
4 HXCOMM DEF(option, HAS_ARG/0, opt_enum, opt_help) is used to construct
5 HXCOMM option structures, enums and help message.
6 HXCOMM HXCOMM can be used for comments, discarded from both texi and C
7
8 DEFHEADING(Standard options:)
9 STEXI
10 @table @option
11 ETEXI
12
13 DEF("help", 0, QEMU_OPTION_h,
14 "-h or -help display this help and exit\n")
15 STEXI
16 @item -h
17 Display help and exit
18 ETEXI
19
20 DEF("version", 0, QEMU_OPTION_version,
21 "-version display version information and exit\n")
22 STEXI
23 @item -version
24 Display version information and exit
25 ETEXI
26
27 DEF("M", HAS_ARG, QEMU_OPTION_M,
28 "-M machine select emulated machine (-M ? for list)\n")
29 STEXI
30 @item -M @var{machine}
31 Select the emulated @var{machine} (@code{-M ?} for list)
32 ETEXI
33
34 DEF("cpu", HAS_ARG, QEMU_OPTION_cpu,
35 "-cpu cpu select CPU (-cpu ? for list)\n")
36 STEXI
37 @item -cpu @var{model}
38 Select CPU model (-cpu ? for list and additional feature selection)
39 ETEXI
40
41 DEF("smp", HAS_ARG, QEMU_OPTION_smp,
42 "-smp n[,maxcpus=cpus][,cores=cores][,threads=threads][,sockets=sockets]\n"
43 " set the number of CPUs to 'n' [default=1]\n"
44 " maxcpus= maximum number of total cpus, including\n"
45 " offline CPUs for hotplug etc.\n"
46 " cores= number of CPU cores on one socket\n"
47 " threads= number of threads on one CPU core\n"
48 " sockets= number of discrete sockets in the system\n")
49 STEXI
50 @item -smp @var{n}[,cores=@var{cores}][,threads=@var{threads}][,sockets=@var{sockets}][,maxcpus=@var{maxcpus}]
51 Simulate an SMP system with @var{n} CPUs. On the PC target, up to 255
52 CPUs are supported. On Sparc32 target, Linux limits the number of usable CPUs
53 to 4.
54 For the PC target, the number of @var{cores} per socket, the number
55 of @var{threads} per cores and the total number of @var{sockets} can be
56 specified. Missing values will be computed. If any on the three values is
57 given, the total number of CPUs @var{n} can be omitted. @var{maxcpus}
58 specifies the maximum number of hotpluggable CPUs.
59 ETEXI
60
61 DEF("numa", HAS_ARG, QEMU_OPTION_numa,
62 "-numa node[,mem=size][,cpus=cpu[-cpu]][,nodeid=node]\n")
63 STEXI
64 @item -numa @var{opts}
65 Simulate a multi node NUMA system. If mem and cpus are omitted, resources
66 are split equally.
67 ETEXI
68
69 DEF("fda", HAS_ARG, QEMU_OPTION_fda,
70 "-fda/-fdb file use 'file' as floppy disk 0/1 image\n")
71 DEF("fdb", HAS_ARG, QEMU_OPTION_fdb, "")
72 STEXI
73 @item -fda @var{file}
74 @item -fdb @var{file}
75 Use @var{file} as floppy disk 0/1 image (@pxref{disk_images}). You can
76 use the host floppy by using @file{/dev/fd0} as filename (@pxref{host_drives}).
77 ETEXI
78
79 DEF("hda", HAS_ARG, QEMU_OPTION_hda,
80 "-hda/-hdb file use 'file' as IDE hard disk 0/1 image\n")
81 DEF("hdb", HAS_ARG, QEMU_OPTION_hdb, "")
82 DEF("hdc", HAS_ARG, QEMU_OPTION_hdc,
83 "-hdc/-hdd file use 'file' as IDE hard disk 2/3 image\n")
84 DEF("hdd", HAS_ARG, QEMU_OPTION_hdd, "")
85 STEXI
86 @item -hda @var{file}
87 @item -hdb @var{file}
88 @item -hdc @var{file}
89 @item -hdd @var{file}
90 Use @var{file} as hard disk 0, 1, 2 or 3 image (@pxref{disk_images}).
91 ETEXI
92
93 DEF("cdrom", HAS_ARG, QEMU_OPTION_cdrom,
94 "-cdrom file use 'file' as IDE cdrom image (cdrom is ide1 master)\n")
95 STEXI
96 @item -cdrom @var{file}
97 Use @var{file} as CD-ROM image (you cannot use @option{-hdc} and
98 @option{-cdrom} at the same time). You can use the host CD-ROM by
99 using @file{/dev/cdrom} as filename (@pxref{host_drives}).
100 ETEXI
101
102 DEF("drive", HAS_ARG, QEMU_OPTION_drive,
103 "-drive [file=file][,if=type][,bus=n][,unit=m][,media=d][,index=i]\n"
104 " [,cyls=c,heads=h,secs=s[,trans=t]][,snapshot=on|off]\n"
105 " [,cache=writethrough|writeback|none][,format=f][,serial=s]\n"
106 " [,addr=A][,id=name][,aio=threads|native]\n"
107 " use 'file' as a drive image\n")
108 DEF("set", HAS_ARG, QEMU_OPTION_set,
109 "-set group.id.arg=value\n"
110 " set <arg> parameter for item <id> of type <group>\n"
111 " i.e. -set drive.$id.file=/path/to/image\n")
112 STEXI
113 @item -drive @var{option}[,@var{option}[,@var{option}[,...]]]
114
115 Define a new drive. Valid options are:
116
117 @table @option
118 @item file=@var{file}
119 This option defines which disk image (@pxref{disk_images}) to use with
120 this drive. If the filename contains comma, you must double it
121 (for instance, "file=my,,file" to use file "my,file").
122 @item if=@var{interface}
123 This option defines on which type on interface the drive is connected.
124 Available types are: ide, scsi, sd, mtd, floppy, pflash, virtio.
125 @item bus=@var{bus},unit=@var{unit}
126 These options define where is connected the drive by defining the bus number and
127 the unit id.
128 @item index=@var{index}
129 This option defines where is connected the drive by using an index in the list
130 of available connectors of a given interface type.
131 @item media=@var{media}
132 This option defines the type of the media: disk or cdrom.
133 @item cyls=@var{c},heads=@var{h},secs=@var{s}[,trans=@var{t}]
134 These options have the same definition as they have in @option{-hdachs}.
135 @item snapshot=@var{snapshot}
136 @var{snapshot} is "on" or "off" and allows to enable snapshot for given drive (see @option{-snapshot}).
137 @item cache=@var{cache}
138 @var{cache} is "none", "writeback", or "writethrough" and controls how the host cache is used to access block data.
139 @item aio=@var{aio}
140 @var{aio} is "threads", or "native" and selects between pthread based disk I/O and native Linux AIO.
141 @item format=@var{format}
142 Specify which disk @var{format} will be used rather than detecting
143 the format. Can be used to specifiy format=raw to avoid interpreting
144 an untrusted format header.
145 @item serial=@var{serial}
146 This option specifies the serial number to assign to the device.
147 @item addr=@var{addr}
148 Specify the controller's PCI address (if=virtio only).
149 @end table
150
151 By default, writethrough caching is used for all block device. This means that
152 the host page cache will be used to read and write data but write notification
153 will be sent to the guest only when the data has been reported as written by
154 the storage subsystem.
155
156 Writeback caching will report data writes as completed as soon as the data is
157 present in the host page cache. This is safe as long as you trust your host.
158 If your host crashes or loses power, then the guest may experience data
159 corruption. When using the @option{-snapshot} option, writeback caching is
160 used by default.
161
162 The host page cache can be avoided entirely with @option{cache=none}. This will
163 attempt to do disk IO directly to the guests memory. QEMU may still perform
164 an internal copy of the data.
165
166 Some block drivers perform badly with @option{cache=writethrough}, most notably,
167 qcow2. If performance is more important than correctness,
168 @option{cache=writeback} should be used with qcow2.
169
170 Instead of @option{-cdrom} you can use:
171 @example
172 qemu -drive file=file,index=2,media=cdrom
173 @end example
174
175 Instead of @option{-hda}, @option{-hdb}, @option{-hdc}, @option{-hdd}, you can
176 use:
177 @example
178 qemu -drive file=file,index=0,media=disk
179 qemu -drive file=file,index=1,media=disk
180 qemu -drive file=file,index=2,media=disk
181 qemu -drive file=file,index=3,media=disk
182 @end example
183
184 You can connect a CDROM to the slave of ide0:
185 @example
186 qemu -drive file=file,if=ide,index=1,media=cdrom
187 @end example
188
189 If you don't specify the "file=" argument, you define an empty drive:
190 @example
191 qemu -drive if=ide,index=1,media=cdrom
192 @end example
193
194 You can connect a SCSI disk with unit ID 6 on the bus #0:
195 @example
196 qemu -drive file=file,if=scsi,bus=0,unit=6
197 @end example
198
199 Instead of @option{-fda}, @option{-fdb}, you can use:
200 @example
201 qemu -drive file=file,index=0,if=floppy
202 qemu -drive file=file,index=1,if=floppy
203 @end example
204
205 By default, @var{interface} is "ide" and @var{index} is automatically
206 incremented:
207 @example
208 qemu -drive file=a -drive file=b"
209 @end example
210 is interpreted like:
211 @example
212 qemu -hda a -hdb b
213 @end example
214 ETEXI
215
216 DEF("mtdblock", HAS_ARG, QEMU_OPTION_mtdblock,
217 "-mtdblock file use 'file' as on-board Flash memory image\n")
218 STEXI
219
220 @item -mtdblock @var{file}
221 Use @var{file} as on-board Flash memory image.
222 ETEXI
223
224 DEF("sd", HAS_ARG, QEMU_OPTION_sd,
225 "-sd file use 'file' as SecureDigital card image\n")
226 STEXI
227 @item -sd @var{file}
228 Use @var{file} as SecureDigital card image.
229 ETEXI
230
231 DEF("pflash", HAS_ARG, QEMU_OPTION_pflash,
232 "-pflash file use 'file' as a parallel flash image\n")
233 STEXI
234 @item -pflash @var{file}
235 Use @var{file} as a parallel flash image.
236 ETEXI
237
238 DEF("boot", HAS_ARG, QEMU_OPTION_boot,
239 "-boot [order=drives][,once=drives][,menu=on|off]\n"
240 " 'drives': floppy (a), hard disk (c), CD-ROM (d), network (n)\n")
241 STEXI
242 @item -boot [order=@var{drives}][,once=@var{drives}][,menu=on|off]
243
244 Specify boot order @var{drives} as a string of drive letters. Valid
245 drive letters depend on the target achitecture. The x86 PC uses: a, b
246 (floppy 1 and 2), c (first hard disk), d (first CD-ROM), n-p (Etherboot
247 from network adapter 1-4), hard disk boot is the default. To apply a
248 particular boot order only on the first startup, specify it via
249 @option{once}.
250
251 Interactive boot menus/prompts can be enabled via @option{menu=on} as far
252 as firmware/BIOS supports them. The default is non-interactive boot.
253
254 @example
255 # try to boot from network first, then from hard disk
256 qemu -boot order=nc
257 # boot from CD-ROM first, switch back to default order after reboot
258 qemu -boot once=d
259 @end example
260
261 Note: The legacy format '-boot @var{drives}' is still supported but its
262 use is discouraged as it may be removed from future versions.
263 ETEXI
264
265 DEF("snapshot", 0, QEMU_OPTION_snapshot,
266 "-snapshot write to temporary files instead of disk image files\n")
267 STEXI
268 @item -snapshot
269 Write to temporary files instead of disk image files. In this case,
270 the raw disk image you use is not written back. You can however force
271 the write back by pressing @key{C-a s} (@pxref{disk_images}).
272 ETEXI
273
274 DEF("m", HAS_ARG, QEMU_OPTION_m,
275 "-m megs set virtual RAM size to megs MB [default=%d]\n")
276 STEXI
277 @item -m @var{megs}
278 Set virtual RAM size to @var{megs} megabytes. Default is 128 MiB. Optionally,
279 a suffix of ``M'' or ``G'' can be used to signify a value in megabytes or
280 gigabytes respectively.
281 ETEXI
282
283 DEF("k", HAS_ARG, QEMU_OPTION_k,
284 "-k language use keyboard layout (for example 'fr' for French)\n")
285 STEXI
286 @item -k @var{language}
287
288 Use keyboard layout @var{language} (for example @code{fr} for
289 French). This option is only needed where it is not easy to get raw PC
290 keycodes (e.g. on Macs, with some X11 servers or with a VNC
291 display). You don't normally need to use it on PC/Linux or PC/Windows
292 hosts.
293
294 The available layouts are:
295 @example
296 ar de-ch es fo fr-ca hu ja mk no pt-br sv
297 da en-gb et fr fr-ch is lt nl pl ru th
298 de en-us fi fr-be hr it lv nl-be pt sl tr
299 @end example
300
301 The default is @code{en-us}.
302 ETEXI
303
304
305 #ifdef HAS_AUDIO
306 DEF("audio-help", 0, QEMU_OPTION_audio_help,
307 "-audio-help print list of audio drivers and their options\n")
308 #endif
309 STEXI
310 @item -audio-help
311
312 Will show the audio subsystem help: list of drivers, tunable
313 parameters.
314 ETEXI
315
316 #ifdef HAS_AUDIO
317 DEF("soundhw", HAS_ARG, QEMU_OPTION_soundhw,
318 "-soundhw c1,... enable audio support\n"
319 " and only specified sound cards (comma separated list)\n"
320 " use -soundhw ? to get the list of supported cards\n"
321 " use -soundhw all to enable all of them\n")
322 #endif
323 STEXI
324 @item -soundhw @var{card1}[,@var{card2},...] or -soundhw all
325
326 Enable audio and selected sound hardware. Use ? to print all
327 available sound hardware.
328
329 @example
330 qemu -soundhw sb16,adlib disk.img
331 qemu -soundhw es1370 disk.img
332 qemu -soundhw ac97 disk.img
333 qemu -soundhw all disk.img
334 qemu -soundhw ?
335 @end example
336
337 Note that Linux's i810_audio OSS kernel (for AC97) module might
338 require manually specifying clocking.
339
340 @example
341 modprobe i810_audio clocking=48000
342 @end example
343 ETEXI
344
345 STEXI
346 @end table
347 ETEXI
348
349 DEF("usb", 0, QEMU_OPTION_usb,
350 "-usb enable the USB driver (will be the default soon)\n")
351 STEXI
352 USB options:
353 @table @option
354
355 @item -usb
356 Enable the USB driver (will be the default soon)
357 ETEXI
358
359 DEF("usbdevice", HAS_ARG, QEMU_OPTION_usbdevice,
360 "-usbdevice name add the host or guest USB device 'name'\n")
361 STEXI
362
363 @item -usbdevice @var{devname}
364 Add the USB device @var{devname}. @xref{usb_devices}.
365
366 @table @option
367
368 @item mouse
369 Virtual Mouse. This will override the PS/2 mouse emulation when activated.
370
371 @item tablet
372 Pointer device that uses absolute coordinates (like a touchscreen). This
373 means qemu is able to report the mouse position without having to grab the
374 mouse. Also overrides the PS/2 mouse emulation when activated.
375
376 @item disk:[format=@var{format}]:@var{file}
377 Mass storage device based on file. The optional @var{format} argument
378 will be used rather than detecting the format. Can be used to specifiy
379 @code{format=raw} to avoid interpreting an untrusted format header.
380
381 @item host:@var{bus}.@var{addr}
382 Pass through the host device identified by @var{bus}.@var{addr} (Linux only).
383
384 @item host:@var{vendor_id}:@var{product_id}
385 Pass through the host device identified by @var{vendor_id}:@var{product_id}
386 (Linux only).
387
388 @item serial:[vendorid=@var{vendor_id}][,productid=@var{product_id}]:@var{dev}
389 Serial converter to host character device @var{dev}, see @code{-serial} for the
390 available devices.
391
392 @item braille
393 Braille device. This will use BrlAPI to display the braille output on a real
394 or fake device.
395
396 @item net:@var{options}
397 Network adapter that supports CDC ethernet and RNDIS protocols.
398
399 @end table
400 ETEXI
401
402 DEF("device", HAS_ARG, QEMU_OPTION_device,
403 "-device driver[,options] add device\n")
404 DEF("name", HAS_ARG, QEMU_OPTION_name,
405 "-name string1[,process=string2] set the name of the guest\n"
406 " string1 sets the window title and string2 the process name (on Linux)\n")
407 STEXI
408 @item -name @var{name}
409 Sets the @var{name} of the guest.
410 This name will be displayed in the SDL window caption.
411 The @var{name} will also be used for the VNC server.
412 Also optionally set the top visible process name in Linux.
413 ETEXI
414
415 DEF("uuid", HAS_ARG, QEMU_OPTION_uuid,
416 "-uuid %%08x-%%04x-%%04x-%%04x-%%012x\n"
417 " specify machine UUID\n")
418 STEXI
419 @item -uuid @var{uuid}
420 Set system UUID.
421 ETEXI
422
423 STEXI
424 @end table
425 ETEXI
426
427 DEFHEADING()
428
429 DEFHEADING(Display options:)
430
431 STEXI
432 @table @option
433 ETEXI
434
435 DEF("nographic", 0, QEMU_OPTION_nographic,
436 "-nographic disable graphical output and redirect serial I/Os to console\n")
437 STEXI
438 @item -nographic
439
440 Normally, QEMU uses SDL to display the VGA output. With this option,
441 you can totally disable graphical output so that QEMU is a simple
442 command line application. The emulated serial port is redirected on
443 the console. Therefore, you can still use QEMU to debug a Linux kernel
444 with a serial console.
445 ETEXI
446
447 #ifdef CONFIG_CURSES
448 DEF("curses", 0, QEMU_OPTION_curses,
449 "-curses use a curses/ncurses interface instead of SDL\n")
450 #endif
451 STEXI
452 @item -curses
453
454 Normally, QEMU uses SDL to display the VGA output. With this option,
455 QEMU can display the VGA output when in text mode using a
456 curses/ncurses interface. Nothing is displayed in graphical mode.
457 ETEXI
458
459 #ifdef CONFIG_SDL
460 DEF("no-frame", 0, QEMU_OPTION_no_frame,
461 "-no-frame open SDL window without a frame and window decorations\n")
462 #endif
463 STEXI
464 @item -no-frame
465
466 Do not use decorations for SDL windows and start them using the whole
467 available screen space. This makes the using QEMU in a dedicated desktop
468 workspace more convenient.
469 ETEXI
470
471 #ifdef CONFIG_SDL
472 DEF("alt-grab", 0, QEMU_OPTION_alt_grab,
473 "-alt-grab use Ctrl-Alt-Shift to grab mouse (instead of Ctrl-Alt)\n")
474 #endif
475 STEXI
476 @item -alt-grab
477
478 Use Ctrl-Alt-Shift to grab mouse (instead of Ctrl-Alt).
479 ETEXI
480
481 #ifdef CONFIG_SDL
482 DEF("ctrl-grab", 0, QEMU_OPTION_ctrl_grab,
483 "-ctrl-grab use Right-Ctrl to grab mouse (instead of Ctrl-Alt)\n")
484 #endif
485 STEXI
486 @item -ctrl-grab
487
488 Use Right-Ctrl to grab mouse (instead of Ctrl-Alt).
489 ETEXI
490
491 #ifdef CONFIG_SDL
492 DEF("no-quit", 0, QEMU_OPTION_no_quit,
493 "-no-quit disable SDL window close capability\n")
494 #endif
495 STEXI
496 @item -no-quit
497
498 Disable SDL window close capability.
499 ETEXI
500
501 #ifdef CONFIG_SDL
502 DEF("sdl", 0, QEMU_OPTION_sdl,
503 "-sdl enable SDL\n")
504 #endif
505 STEXI
506 @item -sdl
507
508 Enable SDL.
509 ETEXI
510
511 DEF("portrait", 0, QEMU_OPTION_portrait,
512 "-portrait rotate graphical output 90 deg left (only PXA LCD)\n")
513 STEXI
514 @item -portrait
515
516 Rotate graphical output 90 deg left (only PXA LCD).
517 ETEXI
518
519 DEF("vga", HAS_ARG, QEMU_OPTION_vga,
520 "-vga [std|cirrus|vmware|xenfb|none]\n"
521 " select video card type\n")
522 STEXI
523 @item -vga @var{type}
524 Select type of VGA card to emulate. Valid values for @var{type} are
525 @table @option
526 @item cirrus
527 Cirrus Logic GD5446 Video card. All Windows versions starting from
528 Windows 95 should recognize and use this graphic card. For optimal
529 performances, use 16 bit color depth in the guest and the host OS.
530 (This one is the default)
531 @item std
532 Standard VGA card with Bochs VBE extensions. If your guest OS
533 supports the VESA 2.0 VBE extensions (e.g. Windows XP) and if you want
534 to use high resolution modes (>= 1280x1024x16) then you should use
535 this option.
536 @item vmware
537 VMWare SVGA-II compatible adapter. Use it if you have sufficiently
538 recent XFree86/XOrg server or Windows guest with a driver for this
539 card.
540 @item none
541 Disable VGA card.
542 @end table
543 ETEXI
544
545 DEF("full-screen", 0, QEMU_OPTION_full_screen,
546 "-full-screen start in full screen\n")
547 STEXI
548 @item -full-screen
549 Start in full screen.
550 ETEXI
551
552 #if defined(TARGET_PPC) || defined(TARGET_SPARC)
553 DEF("g", 1, QEMU_OPTION_g ,
554 "-g WxH[xDEPTH] Set the initial graphical resolution and depth\n")
555 #endif
556 STEXI
557 ETEXI
558
559 DEF("vnc", HAS_ARG, QEMU_OPTION_vnc ,
560 "-vnc display start a VNC server on display\n")
561 STEXI
562 @item -vnc @var{display}[,@var{option}[,@var{option}[,...]]]
563
564 Normally, QEMU uses SDL to display the VGA output. With this option,
565 you can have QEMU listen on VNC display @var{display} and redirect the VGA
566 display over the VNC session. It is very useful to enable the usb
567 tablet device when using this option (option @option{-usbdevice
568 tablet}). When using the VNC display, you must use the @option{-k}
569 parameter to set the keyboard layout if you are not using en-us. Valid
570 syntax for the @var{display} is
571
572 @table @option
573
574 @item @var{host}:@var{d}
575
576 TCP connections will only be allowed from @var{host} on display @var{d}.
577 By convention the TCP port is 5900+@var{d}. Optionally, @var{host} can
578 be omitted in which case the server will accept connections from any host.
579
580 @item unix:@var{path}
581
582 Connections will be allowed over UNIX domain sockets where @var{path} is the
583 location of a unix socket to listen for connections on.
584
585 @item none
586
587 VNC is initialized but not started. The monitor @code{change} command
588 can be used to later start the VNC server.
589
590 @end table
591
592 Following the @var{display} value there may be one or more @var{option} flags
593 separated by commas. Valid options are
594
595 @table @option
596
597 @item reverse
598
599 Connect to a listening VNC client via a ``reverse'' connection. The
600 client is specified by the @var{display}. For reverse network
601 connections (@var{host}:@var{d},@code{reverse}), the @var{d} argument
602 is a TCP port number, not a display number.
603
604 @item password
605
606 Require that password based authentication is used for client connections.
607 The password must be set separately using the @code{change} command in the
608 @ref{pcsys_monitor}
609
610 @item tls
611
612 Require that client use TLS when communicating with the VNC server. This
613 uses anonymous TLS credentials so is susceptible to a man-in-the-middle
614 attack. It is recommended that this option be combined with either the
615 @option{x509} or @option{x509verify} options.
616
617 @item x509=@var{/path/to/certificate/dir}
618
619 Valid if @option{tls} is specified. Require that x509 credentials are used
620 for negotiating the TLS session. The server will send its x509 certificate
621 to the client. It is recommended that a password be set on the VNC server
622 to provide authentication of the client when this is used. The path following
623 this option specifies where the x509 certificates are to be loaded from.
624 See the @ref{vnc_security} section for details on generating certificates.
625
626 @item x509verify=@var{/path/to/certificate/dir}
627
628 Valid if @option{tls} is specified. Require that x509 credentials are used
629 for negotiating the TLS session. The server will send its x509 certificate
630 to the client, and request that the client send its own x509 certificate.
631 The server will validate the client's certificate against the CA certificate,
632 and reject clients when validation fails. If the certificate authority is
633 trusted, this is a sufficient authentication mechanism. You may still wish
634 to set a password on the VNC server as a second authentication layer. The
635 path following this option specifies where the x509 certificates are to
636 be loaded from. See the @ref{vnc_security} section for details on generating
637 certificates.
638
639 @item sasl
640
641 Require that the client use SASL to authenticate with the VNC server.
642 The exact choice of authentication method used is controlled from the
643 system / user's SASL configuration file for the 'qemu' service. This
644 is typically found in /etc/sasl2/qemu.conf. If running QEMU as an
645 unprivileged user, an environment variable SASL_CONF_PATH can be used
646 to make it search alternate locations for the service config.
647 While some SASL auth methods can also provide data encryption (eg GSSAPI),
648 it is recommended that SASL always be combined with the 'tls' and
649 'x509' settings to enable use of SSL and server certificates. This
650 ensures a data encryption preventing compromise of authentication
651 credentials. See the @ref{vnc_security} section for details on using
652 SASL authentication.
653
654 @item acl
655
656 Turn on access control lists for checking of the x509 client certificate
657 and SASL party. For x509 certs, the ACL check is made against the
658 certificate's distinguished name. This is something that looks like
659 @code{C=GB,O=ACME,L=Boston,CN=bob}. For SASL party, the ACL check is
660 made against the username, which depending on the SASL plugin, may
661 include a realm component, eg @code{bob} or @code{bob@@EXAMPLE.COM}.
662 When the @option{acl} flag is set, the initial access list will be
663 empty, with a @code{deny} policy. Thus no one will be allowed to
664 use the VNC server until the ACLs have been loaded. This can be
665 achieved using the @code{acl} monitor command.
666
667 @end table
668 ETEXI
669
670 STEXI
671 @end table
672 ETEXI
673
674 DEFHEADING()
675
676 #ifdef TARGET_I386
677 DEFHEADING(i386 target only:)
678 #endif
679 STEXI
680 @table @option
681 ETEXI
682
683 #ifdef TARGET_I386
684 DEF("win2k-hack", 0, QEMU_OPTION_win2k_hack,
685 "-win2k-hack use it when installing Windows 2000 to avoid a disk full bug\n")
686 #endif
687 STEXI
688 @item -win2k-hack
689 Use it when installing Windows 2000 to avoid a disk full bug. After
690 Windows 2000 is installed, you no longer need this option (this option
691 slows down the IDE transfers).
692 ETEXI
693
694 #ifdef TARGET_I386
695 HXCOMM Deprecated by -rtc
696 DEF("rtc-td-hack", 0, QEMU_OPTION_rtc_td_hack, "")
697 #endif
698
699 #ifdef TARGET_I386
700 DEF("no-fd-bootchk", 0, QEMU_OPTION_no_fd_bootchk,
701 "-no-fd-bootchk disable boot signature checking for floppy disks\n")
702 #endif
703 STEXI
704 @item -no-fd-bootchk
705 Disable boot signature checking for floppy disks in Bochs BIOS. It may
706 be needed to boot from old floppy disks.
707 ETEXI
708
709 #ifdef TARGET_I386
710 DEF("no-acpi", 0, QEMU_OPTION_no_acpi,
711 "-no-acpi disable ACPI\n")
712 #endif
713 STEXI
714 @item -no-acpi
715 Disable ACPI (Advanced Configuration and Power Interface) support. Use
716 it if your guest OS complains about ACPI problems (PC target machine
717 only).
718 ETEXI
719
720 #ifdef TARGET_I386
721 DEF("no-hpet", 0, QEMU_OPTION_no_hpet,
722 "-no-hpet disable HPET\n")
723 #endif
724 STEXI
725 @item -no-hpet
726 Disable HPET support.
727 ETEXI
728
729 #ifdef TARGET_I386
730 DEF("balloon", HAS_ARG, QEMU_OPTION_balloon,
731 "-balloon none disable balloon device\n"
732 "-balloon virtio[,addr=str]\n"
733 " enable virtio balloon device (default)\n")
734 #endif
735 STEXI
736 @item -balloon none
737 Disable balloon device.
738 @item -balloon virtio[,addr=@var{addr}]
739 Enable virtio balloon device (default), optionally with PCI address
740 @var{addr}.
741 ETEXI
742
743 #ifdef TARGET_I386
744 DEF("acpitable", HAS_ARG, QEMU_OPTION_acpitable,
745 "-acpitable [sig=str][,rev=n][,oem_id=str][,oem_table_id=str][,oem_rev=n][,asl_compiler_id=str][,asl_compiler_rev=n][,data=file1[:file2]...]\n"
746 " ACPI table description\n")
747 #endif
748 STEXI
749 @item -acpitable [sig=@var{str}][,rev=@var{n}][,oem_id=@var{str}][,oem_table_id=@var{str}][,oem_rev=@var{n}] [,asl_compiler_id=@var{str}][,asl_compiler_rev=@var{n}][,data=@var{file1}[:@var{file2}]...]
750 Add ACPI table with specified header fields and context from specified files.
751 ETEXI
752
753 #ifdef TARGET_I386
754 DEF("smbios", HAS_ARG, QEMU_OPTION_smbios,
755 "-smbios file=binary\n"
756 " Load SMBIOS entry from binary file\n"
757 "-smbios type=0[,vendor=str][,version=str][,date=str][,release=%%d.%%d]\n"
758 " Specify SMBIOS type 0 fields\n"
759 "-smbios type=1[,manufacturer=str][,product=str][,version=str][,serial=str]\n"
760 " [,uuid=uuid][,sku=str][,family=str]\n"
761 " Specify SMBIOS type 1 fields\n")
762 #endif
763 STEXI
764 @item -smbios file=@var{binary}
765 Load SMBIOS entry from binary file.
766
767 @item -smbios type=0[,vendor=@var{str}][,version=@var{str}][,date=@var{str}][,release=@var{%d.%d}]
768 Specify SMBIOS type 0 fields
769
770 @item -smbios type=1[,manufacturer=@var{str}][,product=@var{str}][,version=@var{str}][,serial=@var{str}][,uuid=@var{uuid}][,sku=@var{str}][,family=@var{str}]
771 Specify SMBIOS type 1 fields
772 ETEXI
773
774 #ifdef TARGET_I386
775 DEFHEADING()
776 #endif
777 STEXI
778 @end table
779 ETEXI
780
781 DEFHEADING(Network options:)
782 STEXI
783 @table @option
784 ETEXI
785
786 HXCOMM Legacy slirp options (now moved to -net user):
787 #ifdef CONFIG_SLIRP
788 DEF("tftp", HAS_ARG, QEMU_OPTION_tftp, "")
789 DEF("bootp", HAS_ARG, QEMU_OPTION_bootp, "")
790 DEF("redir", HAS_ARG, QEMU_OPTION_redir, "")
791 #ifndef _WIN32
792 DEF("smb", HAS_ARG, QEMU_OPTION_smb, "")
793 #endif
794 #endif
795
796 DEF("net", HAS_ARG, QEMU_OPTION_net,
797 "-net nic[,vlan=n][,macaddr=mac][,model=type][,name=str][,addr=str][,vectors=v]\n"
798 " create a new Network Interface Card and connect it to VLAN 'n'\n"
799 #ifdef CONFIG_SLIRP
800 "-net user[,vlan=n][,name=str][,net=addr[/mask]][,host=addr][,restrict=y|n]\n"
801 " [,hostname=host][,dhcpstart=addr][,dns=addr][,tftp=dir][,bootfile=f]\n"
802 " [,hostfwd=rule][,guestfwd=rule]"
803 #ifndef _WIN32
804 "[,smb=dir[,smbserver=addr]]\n"
805 #endif
806 " connect the user mode network stack to VLAN 'n', configure its\n"
807 " DHCP server and enabled optional services\n"
808 #endif
809 #ifdef _WIN32
810 "-net tap[,vlan=n][,name=str],ifname=name\n"
811 " connect the host TAP network interface to VLAN 'n'\n"
812 #else
813 "-net tap[,vlan=n][,name=str][,fd=h][,ifname=name][,script=file][,downscript=dfile][,sndbuf=nbytes][,vnet_hdr=on|off]\n"
814 " connect the host TAP network interface to VLAN 'n' and use the\n"
815 " network scripts 'file' (default=%s)\n"
816 " and 'dfile' (default=%s);\n"
817 " use '[down]script=no' to disable script execution;\n"
818 " use 'fd=h' to connect to an already opened TAP interface\n"
819 " use 'sndbuf=nbytes' to limit the size of the send buffer; the\n"
820 " default of 'sndbuf=1048576' can be disabled using 'sndbuf=0'\n"
821 " use vnet_hdr=off to avoid enabling the IFF_VNET_HDR tap flag; use\n"
822 " vnet_hdr=on to make the lack of IFF_VNET_HDR support an error condition\n"
823 #endif
824 "-net socket[,vlan=n][,name=str][,fd=h][,listen=[host]:port][,connect=host:port]\n"
825 " connect the vlan 'n' to another VLAN using a socket connection\n"
826 "-net socket[,vlan=n][,name=str][,fd=h][,mcast=maddr:port]\n"
827 " connect the vlan 'n' to multicast maddr and port\n"
828 #ifdef CONFIG_VDE
829 "-net vde[,vlan=n][,name=str][,sock=socketpath][,port=n][,group=groupname][,mode=octalmode]\n"
830 " connect the vlan 'n' to port 'n' of a vde switch running\n"
831 " on host and listening for incoming connections on 'socketpath'.\n"
832 " Use group 'groupname' and mode 'octalmode' to change default\n"
833 " ownership and permissions for communication port.\n"
834 #endif
835 "-net dump[,vlan=n][,file=f][,len=n]\n"
836 " dump traffic on vlan 'n' to file 'f' (max n bytes per packet)\n"
837 "-net none use it alone to have zero network devices; if no -net option\n"
838 " is provided, the default is '-net nic -net user'\n")
839 DEF("netdev", HAS_ARG, QEMU_OPTION_netdev,
840 "-netdev ["
841 #ifdef CONFIG_SLIRP
842 "user|"
843 #endif
844 "tap|"
845 #ifdef CONFIG_VDE
846 "vde|"
847 #endif
848 "socket],id=str[,option][,option][,...]\n")
849 STEXI
850 @item -net nic[,vlan=@var{n}][,macaddr=@var{mac}][,model=@var{type}][,name=@var{name}][,addr=@var{addr}][,vectors=@var{v}]
851 Create a new Network Interface Card and connect it to VLAN @var{n} (@var{n}
852 = 0 is the default). The NIC is an e1000 by default on the PC
853 target. Optionally, the MAC address can be changed to @var{mac}, the
854 device address set to @var{addr} (PCI cards only),
855 and a @var{name} can be assigned for use in monitor commands.
856 Optionally, for PCI cards, you can specify the number @var{v} of MSI-X vectors
857 that the card should have; this option currently only affects virtio cards; set
858 @var{v} = 0 to disable MSI-X. If no @option{-net} option is specified, a single
859 NIC is created. Qemu can emulate several different models of network card.
860 Valid values for @var{type} are
861 @code{virtio}, @code{i82551}, @code{i82557b}, @code{i82559er},
862 @code{ne2k_pci}, @code{ne2k_isa}, @code{pcnet}, @code{rtl8139},
863 @code{e1000}, @code{smc91c111}, @code{lance} and @code{mcf_fec}.
864 Not all devices are supported on all targets. Use -net nic,model=?
865 for a list of available devices for your target.
866
867 @item -net user[,@var{option}][,@var{option}][,...]
868 Use the user mode network stack which requires no administrator
869 privilege to run. Valid options are:
870
871 @table @option
872 @item vlan=@var{n}
873 Connect user mode stack to VLAN @var{n} (@var{n} = 0 is the default).
874
875 @item name=@var{name}
876 Assign symbolic name for use in monitor commands.
877
878 @item net=@var{addr}[/@var{mask}]
879 Set IP network address the guest will see. Optionally specify the netmask,
880 either in the form a.b.c.d or as number of valid top-most bits. Default is
881 10.0.2.0/8.
882
883 @item host=@var{addr}
884 Specify the guest-visible address of the host. Default is the 2nd IP in the
885 guest network, i.e. x.x.x.2.
886
887 @item restrict=y|yes|n|no
888 If this options is enabled, the guest will be isolated, i.e. it will not be
889 able to contact the host and no guest IP packets will be routed over the host
890 to the outside. This option does not affect explicitly set forwarding rule.
891
892 @item hostname=@var{name}
893 Specifies the client hostname reported by the builtin DHCP server.
894
895 @item dhcpstart=@var{addr}
896 Specify the first of the 16 IPs the built-in DHCP server can assign. Default
897 is the 16th to 31st IP in the guest network, i.e. x.x.x.16 to x.x.x.31.
898
899 @item dns=@var{addr}
900 Specify the guest-visible address of the virtual nameserver. The address must
901 be different from the host address. Default is the 3rd IP in the guest network,
902 i.e. x.x.x.3.
903
904 @item tftp=@var{dir}
905 When using the user mode network stack, activate a built-in TFTP
906 server. The files in @var{dir} will be exposed as the root of a TFTP server.
907 The TFTP client on the guest must be configured in binary mode (use the command
908 @code{bin} of the Unix TFTP client).
909
910 @item bootfile=@var{file}
911 When using the user mode network stack, broadcast @var{file} as the BOOTP
912 filename. In conjunction with @option{tftp}, this can be used to network boot
913 a guest from a local directory.
914
915 Example (using pxelinux):
916 @example
917 qemu -hda linux.img -boot n -net user,tftp=/path/to/tftp/files,bootfile=/pxelinux.0
918 @end example
919
920 @item smb=@var{dir}[,smbserver=@var{addr}]
921 When using the user mode network stack, activate a built-in SMB
922 server so that Windows OSes can access to the host files in @file{@var{dir}}
923 transparently. The IP address of the SMB server can be set to @var{addr}. By
924 default the 4th IP in the guest network is used, i.e. x.x.x.4.
925
926 In the guest Windows OS, the line:
927 @example
928 10.0.2.4 smbserver
929 @end example
930 must be added in the file @file{C:\WINDOWS\LMHOSTS} (for windows 9x/Me)
931 or @file{C:\WINNT\SYSTEM32\DRIVERS\ETC\LMHOSTS} (Windows NT/2000).
932
933 Then @file{@var{dir}} can be accessed in @file{\\smbserver\qemu}.
934
935 Note that a SAMBA server must be installed on the host OS in
936 @file{/usr/sbin/smbd}. QEMU was tested successfully with smbd versions from
937 Red Hat 9, Fedora Core 3 and OpenSUSE 11.x.
938
939 @item hostfwd=[tcp|udp]:[@var{hostaddr}]:@var{hostport}-[@var{guestaddr}]:@var{guestport}
940 Redirect incoming TCP or UDP connections to the host port @var{hostport} to
941 the guest IP address @var{guestaddr} on guest port @var{guestport}. If
942 @var{guestaddr} is not specified, its value is x.x.x.15 (default first address
943 given by the built-in DHCP server). By specifying @var{hostaddr}, the rule can
944 be bound to a specific host interface. If no connection type is set, TCP is
945 used. This option can be given multiple times.
946
947 For example, to redirect host X11 connection from screen 1 to guest
948 screen 0, use the following:
949
950 @example
951 # on the host
952 qemu -net user,hostfwd=tcp:127.0.0.1:6001-:6000 [...]
953 # this host xterm should open in the guest X11 server
954 xterm -display :1
955 @end example
956
957 To redirect telnet connections from host port 5555 to telnet port on
958 the guest, use the following:
959
960 @example
961 # on the host
962 qemu -net user,hostfwd=tcp:5555::23 [...]
963 telnet localhost 5555
964 @end example
965
966 Then when you use on the host @code{telnet localhost 5555}, you
967 connect to the guest telnet server.
968
969 @item guestfwd=[tcp]:@var{server}:@var{port}-@var{dev}
970 Forward guest TCP connections to the IP address @var{server} on port @var{port}
971 to the character device @var{dev}. This option can be given multiple times.
972
973 @end table
974
975 Note: Legacy stand-alone options -tftp, -bootp, -smb and -redir are still
976 processed and applied to -net user. Mixing them with the new configuration
977 syntax gives undefined results. Their use for new applications is discouraged
978 as they will be removed from future versions.
979
980 @item -net tap[,vlan=@var{n}][,name=@var{name}][,fd=@var{h}][,ifname=@var{name}][,script=@var{file}][,downscript=@var{dfile}]
981 Connect the host TAP network interface @var{name} to VLAN @var{n}, use
982 the network script @var{file} to configure it and the network script
983 @var{dfile} to deconfigure it. If @var{name} is not provided, the OS
984 automatically provides one. @option{fd}=@var{h} can be used to specify
985 the handle of an already opened host TAP interface. The default network
986 configure script is @file{/etc/qemu-ifup} and the default network
987 deconfigure script is @file{/etc/qemu-ifdown}. Use @option{script=no}
988 or @option{downscript=no} to disable script execution. Example:
989
990 @example
991 qemu linux.img -net nic -net tap
992 @end example
993
994 More complicated example (two NICs, each one connected to a TAP device)
995 @example
996 qemu linux.img -net nic,vlan=0 -net tap,vlan=0,ifname=tap0 \
997 -net nic,vlan=1 -net tap,vlan=1,ifname=tap1
998 @end example
999
1000 @item -net socket[,vlan=@var{n}][,name=@var{name}][,fd=@var{h}][,listen=[@var{host}]:@var{port}][,connect=@var{host}:@var{port}]
1001
1002 Connect the VLAN @var{n} to a remote VLAN in another QEMU virtual
1003 machine using a TCP socket connection. If @option{listen} is
1004 specified, QEMU waits for incoming connections on @var{port}
1005 (@var{host} is optional). @option{connect} is used to connect to
1006 another QEMU instance using the @option{listen} option. @option{fd}=@var{h}
1007 specifies an already opened TCP socket.
1008
1009 Example:
1010 @example
1011 # launch a first QEMU instance
1012 qemu linux.img -net nic,macaddr=52:54:00:12:34:56 \
1013 -net socket,listen=:1234
1014 # connect the VLAN 0 of this instance to the VLAN 0
1015 # of the first instance
1016 qemu linux.img -net nic,macaddr=52:54:00:12:34:57 \
1017 -net socket,connect=127.0.0.1:1234
1018 @end example
1019
1020 @item -net socket[,vlan=@var{n}][,name=@var{name}][,fd=@var{h}][,mcast=@var{maddr}:@var{port}]
1021
1022 Create a VLAN @var{n} shared with another QEMU virtual
1023 machines using a UDP multicast socket, effectively making a bus for
1024 every QEMU with same multicast address @var{maddr} and @var{port}.
1025 NOTES:
1026 @enumerate
1027 @item
1028 Several QEMU can be running on different hosts and share same bus (assuming
1029 correct multicast setup for these hosts).
1030 @item
1031 mcast support is compatible with User Mode Linux (argument @option{eth@var{N}=mcast}), see
1032 @url{http://user-mode-linux.sf.net}.
1033 @item
1034 Use @option{fd=h} to specify an already opened UDP multicast socket.
1035 @end enumerate
1036
1037 Example:
1038 @example
1039 # launch one QEMU instance
1040 qemu linux.img -net nic,macaddr=52:54:00:12:34:56 \
1041 -net socket,mcast=230.0.0.1:1234
1042 # launch another QEMU instance on same "bus"
1043 qemu linux.img -net nic,macaddr=52:54:00:12:34:57 \
1044 -net socket,mcast=230.0.0.1:1234
1045 # launch yet another QEMU instance on same "bus"
1046 qemu linux.img -net nic,macaddr=52:54:00:12:34:58 \
1047 -net socket,mcast=230.0.0.1:1234
1048 @end example
1049
1050 Example (User Mode Linux compat.):
1051 @example
1052 # launch QEMU instance (note mcast address selected
1053 # is UML's default)
1054 qemu linux.img -net nic,macaddr=52:54:00:12:34:56 \
1055 -net socket,mcast=239.192.168.1:1102
1056 # launch UML
1057 /path/to/linux ubd0=/path/to/root_fs eth0=mcast
1058 @end example
1059
1060 @item -net vde[,vlan=@var{n}][,name=@var{name}][,sock=@var{socketpath}][,port=@var{n}][,group=@var{groupname}][,mode=@var{octalmode}]
1061 Connect VLAN @var{n} to PORT @var{n} of a vde switch running on host and
1062 listening for incoming connections on @var{socketpath}. Use GROUP @var{groupname}
1063 and MODE @var{octalmode} to change default ownership and permissions for
1064 communication port. This option is available only if QEMU has been compiled
1065 with vde support enabled.
1066
1067 Example:
1068 @example
1069 # launch vde switch
1070 vde_switch -F -sock /tmp/myswitch
1071 # launch QEMU instance
1072 qemu linux.img -net nic -net vde,sock=/tmp/myswitch
1073 @end example
1074
1075 @item -net dump[,vlan=@var{n}][,file=@var{file}][,len=@var{len}]
1076 Dump network traffic on VLAN @var{n} to file @var{file} (@file{qemu-vlan0.pcap} by default).
1077 At most @var{len} bytes (64k by default) per packet are stored. The file format is
1078 libpcap, so it can be analyzed with tools such as tcpdump or Wireshark.
1079
1080 @item -net none
1081 Indicate that no network devices should be configured. It is used to
1082 override the default configuration (@option{-net nic -net user}) which
1083 is activated if no @option{-net} options are provided.
1084
1085 @end table
1086 ETEXI
1087
1088 DEFHEADING()
1089
1090 DEFHEADING(Character device options:)
1091
1092 DEF("chardev", HAS_ARG, QEMU_OPTION_chardev,
1093 "-chardev null,id=id\n"
1094 "-chardev socket,id=id[,host=host],port=host[,to=to][,ipv4][,ipv6][,nodelay]\n"
1095 " [,server][,nowait][,telnet] (tcp)\n"
1096 "-chardev socket,id=id,path=path[,server][,nowait][,telnet] (unix)\n"
1097 "-chardev udp,id=id[,host=host],port=port[,localaddr=localaddr]\n"
1098 " [,localport=localport][,ipv4][,ipv6]\n"
1099 "-chardev msmouse,id=id\n"
1100 "-chardev vc,id=id[[,width=width][,height=height]][[,cols=cols][,rows=rows]]\n"
1101 "-chardev file,id=id,path=path\n"
1102 "-chardev pipe,id=id,path=path\n"
1103 #ifdef _WIN32
1104 "-chardev console,id=id\n"
1105 "-chardev serial,id=id,path=path\n"
1106 #else
1107 "-chardev pty,id=id\n"
1108 "-chardev stdio,id=id\n"
1109 #endif
1110 #ifdef CONFIG_BRLAPI
1111 "-chardev braille,id=id\n"
1112 #endif
1113 #if defined(__linux__) || defined(__sun__) || defined(__FreeBSD__) \
1114 || defined(__NetBSD__) || defined(__OpenBSD__) || defined(__DragonFly__)
1115 "-chardev tty,id=id,path=path\n"
1116 #endif
1117 #if defined(__linux__) || defined(__FreeBSD__) || defined(__DragonFly__)
1118 "-chardev parport,id=id,path=path\n"
1119 #endif
1120 )
1121
1122 STEXI
1123
1124 The general form of a character device option is:
1125 @table @option
1126
1127 @item -chardev @var{backend} ,id=@var{id} [,@var{options}]
1128
1129 Backend is one of:
1130 @option{null},
1131 @option{socket},
1132 @option{udp},
1133 @option{msmouse},
1134 @option{vc},
1135 @option{file},
1136 @option{pipe},
1137 @option{console},
1138 @option{serial},
1139 @option{pty},
1140 @option{stdio},
1141 @option{braille},
1142 @option{tty},
1143 @option{parport}.
1144 The specific backend will determine the applicable options.
1145
1146 All devices must have an id, which can be any string up to 127 characters long.
1147 It is used to uniquely identify this device in other command line directives.
1148
1149 Options to each backend are described below.
1150
1151 @item -chardev null ,id=@var{id}
1152 A void device. This device will not emit any data, and will drop any data it
1153 receives. The null backend does not take any options.
1154
1155 @item -chardev socket ,id=@var{id} [@var{TCP options} or @var{unix options}] [,server] [,nowait] [,telnet]
1156
1157 Create a two-way stream socket, which can be either a TCP or a unix socket. A
1158 unix socket will be created if @option{path} is specified. Behaviour is
1159 undefined if TCP options are specified for a unix socket.
1160
1161 @option{server} specifies that the socket shall be a listening socket.
1162
1163 @option{nowait} specifies that QEMU should not block waiting for a client to
1164 connect to a listening socket.
1165
1166 @option{telnet} specifies that traffic on the socket should interpret telnet
1167 escape sequences.
1168
1169 TCP and unix socket options are given below:
1170
1171 @table @option
1172
1173 @item TCP options: port=@var{host} [,host=@var{host}] [,to=@var{to}] [,ipv4] [,ipv6] [,nodelay]
1174
1175 @option{host} for a listening socket specifies the local address to be bound.
1176 For a connecting socket species the remote host to connect to. @option{host} is
1177 optional for listening sockets. If not specified it defaults to @code{0.0.0.0}.
1178
1179 @option{port} for a listening socket specifies the local port to be bound. For a
1180 connecting socket specifies the port on the remote host to connect to.
1181 @option{port} can be given as either a port number or a service name.
1182 @option{port} is required.
1183
1184 @option{to} is only relevant to listening sockets. If it is specified, and
1185 @option{port} cannot be bound, QEMU will attempt to bind to subsequent ports up
1186 to and including @option{to} until it succeeds. @option{to} must be specified
1187 as a port number.
1188
1189 @option{ipv4} and @option{ipv6} specify that either IPv4 or IPv6 must be used.
1190 If neither is specified the socket may use either protocol.
1191
1192 @option{nodelay} disables the Nagle algorithm.
1193
1194 @item unix options: path=@var{path}
1195
1196 @option{path} specifies the local path of the unix socket. @option{path} is
1197 required.
1198
1199 @end table
1200
1201 @item -chardev udp ,id=@var{id} [,host=@var{host}] ,port=@var{port} [,localaddr=@var{localaddr}] [,localport=@var{localport}] [,ipv4] [,ipv6]
1202
1203 Sends all traffic from the guest to a remote host over UDP.
1204
1205 @option{host} specifies the remote host to connect to. If not specified it
1206 defaults to @code{localhost}.
1207
1208 @option{port} specifies the port on the remote host to connect to. @option{port}
1209 is required.
1210
1211 @option{localaddr} specifies the local address to bind to. If not specified it
1212 defaults to @code{0.0.0.0}.
1213
1214 @option{localport} specifies the local port to bind to. If not specified any
1215 available local port will be used.
1216
1217 @option{ipv4} and @option{ipv6} specify that either IPv4 or IPv6 must be used.
1218 If neither is specified the device may use either protocol.
1219
1220 @item -chardev msmouse ,id=@var{id}
1221
1222 Forward QEMU's emulated msmouse events to the guest. @option{msmouse} does not
1223 take any options.
1224
1225 @item -chardev vc ,id=@var{id} [[,width=@var{width}] [,height=@var{height}]] [[,cols=@var{cols}] [,rows=@var{rows}]]
1226
1227 Connect to a QEMU text console. @option{vc} may optionally be given a specific
1228 size.
1229
1230 @option{width} and @option{height} specify the width and height respectively of
1231 the console, in pixels.
1232
1233 @option{cols} and @option{rows} specify that the console be sized to fit a text
1234 console with the given dimensions.
1235
1236 @item -chardev file ,id=@var{id} ,path=@var{path}
1237
1238 Log all traffic received from the guest to a file.
1239
1240 @option{path} specifies the path of the file to be opened. This file will be
1241 created if it does not already exist, and overwritten if it does. @option{path}
1242 is required.
1243
1244 @item -chardev pipe ,id=@var{id} ,path=@var{path}
1245
1246 Create a two-way connection to the guest. The behaviour differs slightly between
1247 Windows hosts and other hosts:
1248
1249 On Windows, a single duplex pipe will be created at
1250 @file{\\.pipe\@option{path}}.
1251
1252 On other hosts, 2 pipes will be created called @file{@option{path}.in} and
1253 @file{@option{path}.out}. Data written to @file{@option{path}.in} will be
1254 received by the guest. Data written by the guest can be read from
1255 @file{@option{path}.out}. QEMU will not create these fifos, and requires them to
1256 be present.
1257
1258 @option{path} forms part of the pipe path as described above. @option{path} is
1259 required.
1260
1261 @item -chardev console ,id=@var{id}
1262
1263 Send traffic from the guest to QEMU's standard output. @option{console} does not
1264 take any options.
1265
1266 @option{console} is only available on Windows hosts.
1267
1268 @item -chardev serial ,id=@var{id} ,path=@option{path}
1269
1270 Send traffic from the guest to a serial device on the host.
1271
1272 @option{serial} is
1273 only available on Windows hosts.
1274
1275 @option{path} specifies the name of the serial device to open.
1276
1277 @item -chardev pty ,id=@var{id}
1278
1279 Create a new pseudo-terminal on the host and connect to it. @option{pty} does
1280 not take any options.
1281
1282 @option{pty} is not available on Windows hosts.
1283
1284 @item -chardev stdio ,id=@var{id}
1285 Connect to standard input and standard output of the qemu process.
1286 @option{stdio} does not take any options. @option{stdio} is not available on
1287 Windows hosts.
1288
1289 @item -chardev braille ,id=@var{id}
1290
1291 Connect to a local BrlAPI server. @option{braille} does not take any options.
1292
1293 @item -chardev tty ,id=@var{id} ,path=@var{path}
1294
1295 Connect to a local tty device.
1296
1297 @option{tty} is only available on Linux, Sun, FreeBSD, NetBSD, OpenBSD and
1298 DragonFlyBSD hosts.
1299
1300 @option{path} specifies the path to the tty. @option{path} is required.
1301
1302 @item -chardev parport ,id=@var{id} ,path=@var{path}
1303
1304 @option{parport} is only available on Linux, FreeBSD and DragonFlyBSD hosts.
1305
1306 Connect to a local parallel port.
1307
1308 @option{path} specifies the path to the parallel port device. @option{path} is
1309 required.
1310
1311 @end table
1312 ETEXI
1313
1314 DEFHEADING()
1315
1316 DEFHEADING(Bluetooth(R) options:)
1317
1318 DEF("bt", HAS_ARG, QEMU_OPTION_bt, \
1319 "-bt hci,null dumb bluetooth HCI - doesn't respond to commands\n" \
1320 "-bt hci,host[:id]\n" \
1321 " use host's HCI with the given name\n" \
1322 "-bt hci[,vlan=n]\n" \
1323 " emulate a standard HCI in virtual scatternet 'n'\n" \
1324 "-bt vhci[,vlan=n]\n" \
1325 " add host computer to virtual scatternet 'n' using VHCI\n" \
1326 "-bt device:dev[,vlan=n]\n" \
1327 " emulate a bluetooth device 'dev' in scatternet 'n'\n")
1328 STEXI
1329 @table @option
1330
1331 @item -bt hci[...]
1332 Defines the function of the corresponding Bluetooth HCI. -bt options
1333 are matched with the HCIs present in the chosen machine type. For
1334 example when emulating a machine with only one HCI built into it, only
1335 the first @code{-bt hci[...]} option is valid and defines the HCI's
1336 logic. The Transport Layer is decided by the machine type. Currently
1337 the machines @code{n800} and @code{n810} have one HCI and all other
1338 machines have none.
1339
1340 @anchor{bt-hcis}
1341 The following three types are recognized:
1342
1343 @table @option
1344 @item -bt hci,null
1345 (default) The corresponding Bluetooth HCI assumes no internal logic
1346 and will not respond to any HCI commands or emit events.
1347
1348 @item -bt hci,host[:@var{id}]
1349 (@code{bluez} only) The corresponding HCI passes commands / events
1350 to / from the physical HCI identified by the name @var{id} (default:
1351 @code{hci0}) on the computer running QEMU. Only available on @code{bluez}
1352 capable systems like Linux.
1353
1354 @item -bt hci[,vlan=@var{n}]
1355 Add a virtual, standard HCI that will participate in the Bluetooth
1356 scatternet @var{n} (default @code{0}). Similarly to @option{-net}
1357 VLANs, devices inside a bluetooth network @var{n} can only communicate
1358 with other devices in the same network (scatternet).
1359 @end table
1360
1361 @item -bt vhci[,vlan=@var{n}]
1362 (Linux-host only) Create a HCI in scatternet @var{n} (default 0) attached
1363 to the host bluetooth stack instead of to the emulated target. This
1364 allows the host and target machines to participate in a common scatternet
1365 and communicate. Requires the Linux @code{vhci} driver installed. Can
1366 be used as following:
1367
1368 @example
1369 qemu [...OPTIONS...] -bt hci,vlan=5 -bt vhci,vlan=5
1370 @end example
1371
1372 @item -bt device:@var{dev}[,vlan=@var{n}]
1373 Emulate a bluetooth device @var{dev} and place it in network @var{n}
1374 (default @code{0}). QEMU can only emulate one type of bluetooth devices
1375 currently:
1376
1377 @table @option
1378 @item keyboard
1379 Virtual wireless keyboard implementing the HIDP bluetooth profile.
1380 @end table
1381 @end table
1382 ETEXI
1383
1384 DEFHEADING()
1385
1386 DEFHEADING(Linux/Multiboot boot specific:)
1387 STEXI
1388
1389 When using these options, you can use a given Linux or Multiboot
1390 kernel without installing it in the disk image. It can be useful
1391 for easier testing of various kernels.
1392
1393 @table @option
1394 ETEXI
1395
1396 DEF("kernel", HAS_ARG, QEMU_OPTION_kernel, \
1397 "-kernel bzImage use 'bzImage' as kernel image\n")
1398 STEXI
1399 @item -kernel @var{bzImage}
1400 Use @var{bzImage} as kernel image. The kernel can be either a Linux kernel
1401 or in multiboot format.
1402 ETEXI
1403
1404 DEF("append", HAS_ARG, QEMU_OPTION_append, \
1405 "-append cmdline use 'cmdline' as kernel command line\n")
1406 STEXI
1407 @item -append @var{cmdline}
1408 Use @var{cmdline} as kernel command line
1409 ETEXI
1410
1411 DEF("initrd", HAS_ARG, QEMU_OPTION_initrd, \
1412 "-initrd file use 'file' as initial ram disk\n")
1413 STEXI
1414 @item -initrd @var{file}
1415 Use @var{file} as initial ram disk.
1416
1417 @item -initrd "@var{file1} arg=foo,@var{file2}"
1418
1419 This syntax is only available with multiboot.
1420
1421 Use @var{file1} and @var{file2} as modules and pass arg=foo as parameter to the
1422 first module.
1423 ETEXI
1424
1425 STEXI
1426 @end table
1427 ETEXI
1428
1429 DEFHEADING()
1430
1431 DEFHEADING(Debug/Expert options:)
1432
1433 STEXI
1434 @table @option
1435 ETEXI
1436
1437 DEF("serial", HAS_ARG, QEMU_OPTION_serial, \
1438 "-serial dev redirect the serial port to char device 'dev'\n")
1439 STEXI
1440 @item -serial @var{dev}
1441 Redirect the virtual serial port to host character device
1442 @var{dev}. The default device is @code{vc} in graphical mode and
1443 @code{stdio} in non graphical mode.
1444
1445 This option can be used several times to simulate up to 4 serial
1446 ports.
1447
1448 Use @code{-serial none} to disable all serial ports.
1449
1450 Available character devices are:
1451 @table @option
1452 @item vc[:@var{W}x@var{H}]
1453 Virtual console. Optionally, a width and height can be given in pixel with
1454 @example
1455 vc:800x600
1456 @end example
1457 It is also possible to specify width or height in characters:
1458 @example
1459 vc:80Cx24C
1460 @end example
1461 @item pty
1462 [Linux only] Pseudo TTY (a new PTY is automatically allocated)
1463 @item none
1464 No device is allocated.
1465 @item null
1466 void device
1467 @item /dev/XXX
1468 [Linux only] Use host tty, e.g. @file{/dev/ttyS0}. The host serial port
1469 parameters are set according to the emulated ones.
1470 @item /dev/parport@var{N}
1471 [Linux only, parallel port only] Use host parallel port
1472 @var{N}. Currently SPP and EPP parallel port features can be used.
1473 @item file:@var{filename}
1474 Write output to @var{filename}. No character can be read.
1475 @item stdio
1476 [Unix only] standard input/output
1477 @item pipe:@var{filename}
1478 name pipe @var{filename}
1479 @item COM@var{n}
1480 [Windows only] Use host serial port @var{n}
1481 @item udp:[@var{remote_host}]:@var{remote_port}[@@[@var{src_ip}]:@var{src_port}]
1482 This implements UDP Net Console.
1483 When @var{remote_host} or @var{src_ip} are not specified
1484 they default to @code{0.0.0.0}.
1485 When not using a specified @var{src_port} a random port is automatically chosen.
1486
1487 If you just want a simple readonly console you can use @code{netcat} or
1488 @code{nc}, by starting qemu with: @code{-serial udp::4555} and nc as:
1489 @code{nc -u -l -p 4555}. Any time qemu writes something to that port it
1490 will appear in the netconsole session.
1491
1492 If you plan to send characters back via netconsole or you want to stop
1493 and start qemu a lot of times, you should have qemu use the same
1494 source port each time by using something like @code{-serial
1495 udp::4555@@:4556} to qemu. Another approach is to use a patched
1496 version of netcat which can listen to a TCP port and send and receive
1497 characters via udp. If you have a patched version of netcat which
1498 activates telnet remote echo and single char transfer, then you can
1499 use the following options to step up a netcat redirector to allow
1500 telnet on port 5555 to access the qemu port.
1501 @table @code
1502 @item Qemu Options:
1503 -serial udp::4555@@:4556
1504 @item netcat options:
1505 -u -P 4555 -L 0.0.0.0:4556 -t -p 5555 -I -T
1506 @item telnet options:
1507 localhost 5555
1508 @end table
1509
1510 @item tcp:[@var{host}]:@var{port}[,@var{server}][,nowait][,nodelay]
1511 The TCP Net Console has two modes of operation. It can send the serial
1512 I/O to a location or wait for a connection from a location. By default
1513 the TCP Net Console is sent to @var{host} at the @var{port}. If you use
1514 the @var{server} option QEMU will wait for a client socket application
1515 to connect to the port before continuing, unless the @code{nowait}
1516 option was specified. The @code{nodelay} option disables the Nagle buffering
1517 algorithm. If @var{host} is omitted, 0.0.0.0 is assumed. Only
1518 one TCP connection at a time is accepted. You can use @code{telnet} to
1519 connect to the corresponding character device.
1520 @table @code
1521 @item Example to send tcp console to 192.168.0.2 port 4444
1522 -serial tcp:192.168.0.2:4444
1523 @item Example to listen and wait on port 4444 for connection
1524 -serial tcp::4444,server
1525 @item Example to not wait and listen on ip 192.168.0.100 port 4444
1526 -serial tcp:192.168.0.100:4444,server,nowait
1527 @end table
1528
1529 @item telnet:@var{host}:@var{port}[,server][,nowait][,nodelay]
1530 The telnet protocol is used instead of raw tcp sockets. The options
1531 work the same as if you had specified @code{-serial tcp}. The
1532 difference is that the port acts like a telnet server or client using
1533 telnet option negotiation. This will also allow you to send the
1534 MAGIC_SYSRQ sequence if you use a telnet that supports sending the break
1535 sequence. Typically in unix telnet you do it with Control-] and then
1536 type "send break" followed by pressing the enter key.
1537
1538 @item unix:@var{path}[,server][,nowait]
1539 A unix domain socket is used instead of a tcp socket. The option works the
1540 same as if you had specified @code{-serial tcp} except the unix domain socket
1541 @var{path} is used for connections.
1542
1543 @item mon:@var{dev_string}
1544 This is a special option to allow the monitor to be multiplexed onto
1545 another serial port. The monitor is accessed with key sequence of
1546 @key{Control-a} and then pressing @key{c}. See monitor access
1547 @ref{pcsys_keys} in the -nographic section for more keys.
1548 @var{dev_string} should be any one of the serial devices specified
1549 above. An example to multiplex the monitor onto a telnet server
1550 listening on port 4444 would be:
1551 @table @code
1552 @item -serial mon:telnet::4444,server,nowait
1553 @end table
1554
1555 @item braille
1556 Braille device. This will use BrlAPI to display the braille output on a real
1557 or fake device.
1558
1559 @item msmouse
1560 Three button serial mouse. Configure the guest to use Microsoft protocol.
1561 @end table
1562 ETEXI
1563
1564 DEF("parallel", HAS_ARG, QEMU_OPTION_parallel, \
1565 "-parallel dev redirect the parallel port to char device 'dev'\n")
1566 STEXI
1567 @item -parallel @var{dev}
1568 Redirect the virtual parallel port to host device @var{dev} (same
1569 devices as the serial port). On Linux hosts, @file{/dev/parportN} can
1570 be used to use hardware devices connected on the corresponding host
1571 parallel port.
1572
1573 This option can be used several times to simulate up to 3 parallel
1574 ports.
1575
1576 Use @code{-parallel none} to disable all parallel ports.
1577 ETEXI
1578
1579 DEF("monitor", HAS_ARG, QEMU_OPTION_monitor, \
1580 "-monitor [control,]dev redirect the monitor to char device 'dev'\n")
1581 STEXI
1582 @item -monitor [@var{control},]@var{dev}
1583 Redirect the monitor to host device @var{dev} (same devices as the
1584 serial port).
1585 The default device is @code{vc} in graphical mode and @code{stdio} in
1586 non graphical mode.
1587 The option @var{control} enables the QEMU Monitor Protocol.
1588 ETEXI
1589
1590 DEF("pidfile", HAS_ARG, QEMU_OPTION_pidfile, \
1591 "-pidfile file write PID to 'file'\n")
1592 STEXI
1593 @item -pidfile @var{file}
1594 Store the QEMU process PID in @var{file}. It is useful if you launch QEMU
1595 from a script.
1596 ETEXI
1597
1598 DEF("singlestep", 0, QEMU_OPTION_singlestep, \
1599 "-singlestep always run in singlestep mode\n")
1600 STEXI
1601 @item -singlestep
1602 Run the emulation in single step mode.
1603 ETEXI
1604
1605 DEF("S", 0, QEMU_OPTION_S, \
1606 "-S freeze CPU at startup (use 'c' to start execution)\n")
1607 STEXI
1608 @item -S
1609 Do not start CPU at startup (you must type 'c' in the monitor).
1610 ETEXI
1611
1612 DEF("gdb", HAS_ARG, QEMU_OPTION_gdb, \
1613 "-gdb dev wait for gdb connection on 'dev'\n")
1614 STEXI
1615 @item -gdb @var{dev}
1616 Wait for gdb connection on device @var{dev} (@pxref{gdb_usage}). Typical
1617 connections will likely be TCP-based, but also UDP, pseudo TTY, or even
1618 stdio are reasonable use case. The latter is allowing to start qemu from
1619 within gdb and establish the connection via a pipe:
1620 @example
1621 (gdb) target remote | exec qemu -gdb stdio ...
1622 @end example
1623 ETEXI
1624
1625 DEF("s", 0, QEMU_OPTION_s, \
1626 "-s shorthand for -gdb tcp::%s\n")
1627 STEXI
1628 @item -s
1629 Shorthand for -gdb tcp::1234, i.e. open a gdbserver on TCP port 1234
1630 (@pxref{gdb_usage}).
1631 ETEXI
1632
1633 DEF("d", HAS_ARG, QEMU_OPTION_d, \
1634 "-d item1,... output log to %s (use -d ? for a list of log items)\n")
1635 STEXI
1636 @item -d
1637 Output log in /tmp/qemu.log
1638 ETEXI
1639
1640 DEF("hdachs", HAS_ARG, QEMU_OPTION_hdachs, \
1641 "-hdachs c,h,s[,t]\n" \
1642 " force hard disk 0 physical geometry and the optional BIOS\n" \
1643 " translation (t=none or lba) (usually qemu can guess them)\n")
1644 STEXI
1645 @item -hdachs @var{c},@var{h},@var{s},[,@var{t}]
1646 Force hard disk 0 physical geometry (1 <= @var{c} <= 16383, 1 <=
1647 @var{h} <= 16, 1 <= @var{s} <= 63) and optionally force the BIOS
1648 translation mode (@var{t}=none, lba or auto). Usually QEMU can guess
1649 all those parameters. This option is useful for old MS-DOS disk
1650 images.
1651 ETEXI
1652
1653 DEF("L", HAS_ARG, QEMU_OPTION_L, \
1654 "-L path set the directory for the BIOS, VGA BIOS and keymaps\n")
1655 STEXI
1656 @item -L @var{path}
1657 Set the directory for the BIOS, VGA BIOS and keymaps.
1658 ETEXI
1659
1660 DEF("bios", HAS_ARG, QEMU_OPTION_bios, \
1661 "-bios file set the filename for the BIOS\n")
1662 STEXI
1663 @item -bios @var{file}
1664 Set the filename for the BIOS.
1665 ETEXI
1666
1667 #ifdef CONFIG_KVM
1668 DEF("enable-kvm", 0, QEMU_OPTION_enable_kvm, \
1669 "-enable-kvm enable KVM full virtualization support\n")
1670 #endif
1671 STEXI
1672 @item -enable-kvm
1673 Enable KVM full virtualization support. This option is only available
1674 if KVM support is enabled when compiling.
1675 ETEXI
1676
1677 #ifdef CONFIG_XEN
1678 DEF("xen-domid", HAS_ARG, QEMU_OPTION_xen_domid,
1679 "-xen-domid id specify xen guest domain id\n")
1680 DEF("xen-create", 0, QEMU_OPTION_xen_create,
1681 "-xen-create create domain using xen hypercalls, bypassing xend\n"
1682 " warning: should not be used when xend is in use\n")
1683 DEF("xen-attach", 0, QEMU_OPTION_xen_attach,
1684 "-xen-attach attach to existing xen domain\n"
1685 " xend will use this when starting qemu\n")
1686 #endif
1687
1688 DEF("no-reboot", 0, QEMU_OPTION_no_reboot, \
1689 "-no-reboot exit instead of rebooting\n")
1690 STEXI
1691 @item -no-reboot
1692 Exit instead of rebooting.
1693 ETEXI
1694
1695 DEF("no-shutdown", 0, QEMU_OPTION_no_shutdown, \
1696 "-no-shutdown stop before shutdown\n")
1697 STEXI
1698 @item -no-shutdown
1699 Don't exit QEMU on guest shutdown, but instead only stop the emulation.
1700 This allows for instance switching to monitor to commit changes to the
1701 disk image.
1702 ETEXI
1703
1704 DEF("loadvm", HAS_ARG, QEMU_OPTION_loadvm, \
1705 "-loadvm [tag|id]\n" \
1706 " start right away with a saved state (loadvm in monitor)\n")
1707 STEXI
1708 @item -loadvm @var{file}
1709 Start right away with a saved state (@code{loadvm} in monitor)
1710 ETEXI
1711
1712 #ifndef _WIN32
1713 DEF("daemonize", 0, QEMU_OPTION_daemonize, \
1714 "-daemonize daemonize QEMU after initializing\n")
1715 #endif
1716 STEXI
1717 @item -daemonize
1718 Daemonize the QEMU process after initialization. QEMU will not detach from
1719 standard IO until it is ready to receive connections on any of its devices.
1720 This option is a useful way for external programs to launch QEMU without having
1721 to cope with initialization race conditions.
1722 ETEXI
1723
1724 DEF("option-rom", HAS_ARG, QEMU_OPTION_option_rom, \
1725 "-option-rom rom load a file, rom, into the option ROM space\n")
1726 STEXI
1727 @item -option-rom @var{file}
1728 Load the contents of @var{file} as an option ROM.
1729 This option is useful to load things like EtherBoot.
1730 ETEXI
1731
1732 DEF("clock", HAS_ARG, QEMU_OPTION_clock, \
1733 "-clock force the use of the given methods for timer alarm.\n" \
1734 " To see what timers are available use -clock ?\n")
1735 STEXI
1736 @item -clock @var{method}
1737 Force the use of the given methods for timer alarm. To see what timers
1738 are available use -clock ?.
1739 ETEXI
1740
1741 HXCOMM Options deprecated by -rtc
1742 DEF("localtime", 0, QEMU_OPTION_localtime, "")
1743 DEF("startdate", HAS_ARG, QEMU_OPTION_startdate, "")
1744
1745 #ifdef TARGET_I386
1746 DEF("rtc", HAS_ARG, QEMU_OPTION_rtc, \
1747 "-rtc [base=utc|localtime|date][,clock=host|vm][,driftfix=none|slew]\n" \
1748 " set the RTC base and clock, enable drift fix for clock ticks\n")
1749 #else
1750 DEF("rtc", HAS_ARG, QEMU_OPTION_rtc, \
1751 "-rtc [base=utc|localtime|date][,clock=host|vm]\n" \
1752 " set the RTC base and clock\n")
1753 #endif
1754
1755 STEXI
1756
1757 @item -rtc [base=utc|localtime|@var{date}][,clock=host|vm][,driftfix=none|slew]
1758 Specify @option{base} as @code{utc} or @code{localtime} to let the RTC start at the current
1759 UTC or local time, respectively. @code{localtime} is required for correct date in
1760 MS-DOS or Windows. To start at a specific point in time, provide @var{date} in the
1761 format @code{2006-06-17T16:01:21} or @code{2006-06-17}. The default base is UTC.
1762
1763 By default the RTC is driven by the host system time. This allows to use the
1764 RTC as accurate reference clock inside the guest, specifically if the host
1765 time is smoothly following an accurate external reference clock, e.g. via NTP.
1766 If you want to isolate the guest time from the host, even prevent it from
1767 progressing during suspension, you can set @option{clock} to @code{vm} instead.
1768
1769 Enable @option{driftfix} (i386 targets only) if you experience time drift problems,
1770 specifically with Windows' ACPI HAL. This option will try to figure out how
1771 many timer interrupts were not processed by the Windows guest and will
1772 re-inject them.
1773 ETEXI
1774
1775 DEF("icount", HAS_ARG, QEMU_OPTION_icount, \
1776 "-icount [N|auto]\n" \
1777 " enable virtual instruction counter with 2^N clock ticks per\n" \
1778 " instruction\n")
1779 STEXI
1780 @item -icount [@var{N}|auto]
1781 Enable virtual instruction counter. The virtual cpu will execute one
1782 instruction every 2^@var{N} ns of virtual time. If @code{auto} is specified
1783 then the virtual cpu speed will be automatically adjusted to keep virtual
1784 time within a few seconds of real time.
1785
1786 Note that while this option can give deterministic behavior, it does not
1787 provide cycle accurate emulation. Modern CPUs contain superscalar out of
1788 order cores with complex cache hierarchies. The number of instructions
1789 executed often has little or no correlation with actual performance.
1790 ETEXI
1791
1792 DEF("watchdog", HAS_ARG, QEMU_OPTION_watchdog, \
1793 "-watchdog i6300esb|ib700\n" \
1794 " enable virtual hardware watchdog [default=none]\n")
1795 STEXI
1796 @item -watchdog @var{model}
1797 Create a virtual hardware watchdog device. Once enabled (by a guest
1798 action), the watchdog must be periodically polled by an agent inside
1799 the guest or else the guest will be restarted.
1800
1801 The @var{model} is the model of hardware watchdog to emulate. Choices
1802 for model are: @code{ib700} (iBASE 700) which is a very simple ISA
1803 watchdog with a single timer, or @code{i6300esb} (Intel 6300ESB I/O
1804 controller hub) which is a much more featureful PCI-based dual-timer
1805 watchdog. Choose a model for which your guest has drivers.
1806
1807 Use @code{-watchdog ?} to list available hardware models. Only one
1808 watchdog can be enabled for a guest.
1809 ETEXI
1810
1811 DEF("watchdog-action", HAS_ARG, QEMU_OPTION_watchdog_action, \
1812 "-watchdog-action reset|shutdown|poweroff|pause|debug|none\n" \
1813 " action when watchdog fires [default=reset]\n")
1814 STEXI
1815 @item -watchdog-action @var{action}
1816
1817 The @var{action} controls what QEMU will do when the watchdog timer
1818 expires.
1819 The default is
1820 @code{reset} (forcefully reset the guest).
1821 Other possible actions are:
1822 @code{shutdown} (attempt to gracefully shutdown the guest),
1823 @code{poweroff} (forcefully poweroff the guest),
1824 @code{pause} (pause the guest),
1825 @code{debug} (print a debug message and continue), or
1826 @code{none} (do nothing).
1827
1828 Note that the @code{shutdown} action requires that the guest responds
1829 to ACPI signals, which it may not be able to do in the sort of
1830 situations where the watchdog would have expired, and thus
1831 @code{-watchdog-action shutdown} is not recommended for production use.
1832
1833 Examples:
1834
1835 @table @code
1836 @item -watchdog i6300esb -watchdog-action pause
1837 @item -watchdog ib700
1838 @end table
1839 ETEXI
1840
1841 DEF("echr", HAS_ARG, QEMU_OPTION_echr, \
1842 "-echr chr set terminal escape character instead of ctrl-a\n")
1843 STEXI
1844
1845 @item -echr @var{numeric_ascii_value}
1846 Change the escape character used for switching to the monitor when using
1847 monitor and serial sharing. The default is @code{0x01} when using the
1848 @code{-nographic} option. @code{0x01} is equal to pressing
1849 @code{Control-a}. You can select a different character from the ascii
1850 control keys where 1 through 26 map to Control-a through Control-z. For
1851 instance you could use the either of the following to change the escape
1852 character to Control-t.
1853 @table @code
1854 @item -echr 0x14
1855 @item -echr 20
1856 @end table
1857 ETEXI
1858
1859 DEF("virtioconsole", HAS_ARG, QEMU_OPTION_virtiocon, \
1860 "-virtioconsole c\n" \
1861 " set virtio console\n")
1862 STEXI
1863 @item -virtioconsole @var{c}
1864 Set virtio console.
1865 ETEXI
1866
1867 DEF("show-cursor", 0, QEMU_OPTION_show_cursor, \
1868 "-show-cursor show cursor\n")
1869 STEXI
1870 ETEXI
1871
1872 DEF("tb-size", HAS_ARG, QEMU_OPTION_tb_size, \
1873 "-tb-size n set TB size\n")
1874 STEXI
1875 ETEXI
1876
1877 DEF("incoming", HAS_ARG, QEMU_OPTION_incoming, \
1878 "-incoming p prepare for incoming migration, listen on port p\n")
1879 STEXI
1880 ETEXI
1881
1882 #ifndef _WIN32
1883 DEF("chroot", HAS_ARG, QEMU_OPTION_chroot, \
1884 "-chroot dir Chroot to dir just before starting the VM.\n")
1885 #endif
1886 STEXI
1887 @item -chroot @var{dir}
1888 Immediately before starting guest execution, chroot to the specified
1889 directory. Especially useful in combination with -runas.
1890 ETEXI
1891
1892 #ifndef _WIN32
1893 DEF("runas", HAS_ARG, QEMU_OPTION_runas, \
1894 "-runas user Change to user id user just before starting the VM.\n")
1895 #endif
1896 STEXI
1897 @item -runas @var{user}
1898 Immediately before starting guest execution, drop root privileges, switching
1899 to the specified user.
1900 ETEXI
1901
1902 STEXI
1903 @end table
1904 ETEXI
1905
1906 #if defined(TARGET_SPARC) || defined(TARGET_PPC)
1907 DEF("prom-env", HAS_ARG, QEMU_OPTION_prom_env,
1908 "-prom-env variable=value\n"
1909 " set OpenBIOS nvram variables\n")
1910 #endif
1911 #if defined(TARGET_ARM) || defined(TARGET_M68K)
1912 DEF("semihosting", 0, QEMU_OPTION_semihosting,
1913 "-semihosting semihosting mode\n")
1914 #endif
1915 #if defined(TARGET_ARM)
1916 DEF("old-param", 0, QEMU_OPTION_old_param,
1917 "-old-param old param mode\n")
1918 #endif
1919 DEF("readconfig", HAS_ARG, QEMU_OPTION_readconfig,
1920 "-readconfig <file>\n")
1921 DEF("writeconfig", HAS_ARG, QEMU_OPTION_writeconfig,
1922 "-writeconfig <file>\n"
1923 " read/write config file")