lib/bpf: Check return value of write()

This is merely to silence the compiler warning. If write to stderr
failed, assume that printing an error message will fail as well so don't
even try.

Signed-off-by: Phil Sutter <phil@nwl.cc>

diff --git a/lib/bpf.c b/lib/bpf.c
index 09551990dd707b9526776b8ab5447b799ba92022..0bd0a95eafe6cbc6309784c61a796f82c3869be7 100644 (file)
--- a/lib/bpf.c
+++ b/lib/bpf.c
@@ -591,7 +591,8 @@ int bpf_trace_pipe(void)
 
                ret = read(fd, buff, sizeof(buff) - 1);
                if (ret > 0) {
-                       write(2, buff, ret);
+                       if (write(STDERR_FILENO, buff, ret) != ret)
+                               return -1;
                        fflush(stderr);
                }
        }