NAME
setproctitle
setproctitle_fast —
set process title
SYNOPSIS
#include
<sys/types.h>
#include <unistd.h>
void
setproctitle(const
char *fmt,
...);
void
setproctitle_fast(const
char *fmt,
...);
DESCRIPTION
Thesetproctitle()
library routine sets the process title that appears on the
ps(1)
command. The
setproctitle_fast()
variant is optimized for high frequency updates, but may make the
ps(1)
command slightly slower by not updating the kernel cache of the program
arguments.
The title is set from the executable's name, followed by the result of a printf(3) style expansion of the arguments as specified by the fmt argument. If the fmt argument begins with a “-” character, the executable's name is skipped.
If fmt is NULL, the process title is restored.
EXAMPLES
To set the title on a daemon to indicate its activity:
setproctitle("talking to %s", inet_ntoa(addr));
SEE ALSO
ps(1), w(1), setprogname(3), kvm(3), kvm_getargv(3), printf(3)
STANDARDS
The setproctitle() function is implicitly
non-standard. Other methods of causing the
ps(1)
command line to change, including copying over the argv[0] string are also
implicitly non-portable. It is preferable to use an operating system
supplied setproctitle() if present.
Unfortunately, it is possible that there are other calling
conventions to other versions of setproctitle(),
although none have been found by the author as yet. This is believed to be
the predominant convention.
It is thought that the implementation is compatible with other systems, including NetBSD and BSD/OS.
HISTORY
The setproctitle() function first appeared
in FreeBSD 2.2. The
setproctitle_fast() function first appeared in
FreeBSD 12. Other operating systems have similar
functions.
AUTHORS
Peter Wemm <peter@FreeBSD.org> stole the idea from the Sendmail 8.7.3 source code by Eric Allman <eric@sendmail.org>.
BUGS
Never pass a string with user-supplied data as a format without
using ‘%s’. An attacker can put format
specifiers in the string to mangle your stack, leading to a possible
security hole. This holds true even if the string was built using a function
like snprintf(), as the resulting string may still
contain user-supplied conversion specifiers for later interpolation by
setproctitle().
Always use the proper secure idiom:
setproctitle("%s",
string);