man/sd-readahead.3

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  22 .SH "NAME"
  23 sd-readahead \- Reference implementation of APIs for controlling boot\-time read\-ahead
  24 .SH "SYNOPSIS"
  25 .sp
  26 .ft B
  27 .nf
  28 #include "sd\-readahead\&.h"
  29 .fi
  30 .ft
  31 .SH "DESCRIPTION"
  32 .PP
  33 sd\-readahead\&.c
  34 and
  35 sd\-readahead\&.h
  36 provide a reference implementation for APIs for controlling boot\-time read\-ahead, as implemented by the read\-ahead subsystem of the
  37 \fBsystemd\fR(1)
  38 init system\&.
  39 .PP
  40 See
  41 \fBsd_readahead\fR(3)
  42 for more information about the function implemented\&.
  43 .SH "NOTES"
  44 .PP
  45 This interface is provided by the reference implementation of APIs for controlling boot\-time read\-ahead and distributed with the systemd package\&. The algorithms it implements are simple, and can easily be reimplemented in daemons if it is important to support this interface without using the reference implementation\&. See the respective function man pages for details\&.
  46 .PP
  47 In addition, for details about the algorithms, check the liberally licensed reference implementation sources:
  48 \m[blue]\fB\%http://cgit.freedesktop.org/systemd/systemd/plain/src/readahead/sd-readahead.c\fR\m[]
  49 and
  50 \m[blue]\fB\%http://cgit.freedesktop.org/systemd/systemd/plain/src/systemd/sd-readahead.h\fR\m[]
  51 .PP
  52 These APIs are implemented in the reference implementation\*(Aqs drop\-in
  53 sd\-readahead\&.c
  54 and
  55 sd\-readahead\&.h
  56 files\&. It is recommended that applications consuming these APIs copy the implementation into their source tree, either verbatim or in excerpts\&. These interfaces are currently not available in a dynamic library\&.
  57 .PP
  58 The functions provided by this interface become NOPs when \-DDISABLE_SYSTEMD is set during compilation\&. In addition, if
  59 sd\-readhead\&.c
  60 is compiled on non\-Linux systems it becomes NOPs\&.
  61 .SH "SEE ALSO"
  62 .PP
  63 \fBsystemd\fR(1),
  64 \fBsd_readahead\fR(3),
  65 \fBsd-daemon\fR(3)