SYSEXITS(3) NetBSD Library Functions Manual SYSEXITS(3)
NAME
sysexits -- preferable exit codes for programs
SYNOPSIS
#include <sysexits.h>
DESCRIPTION
It is not a good practice to call exit(3) with arbitrary values to indi-
cate a failure condition when ending a program. In addition to the two
standard constants in <stdlib.h>, EXIT_SUCCESS and EXIT_FAILURE, the
header <sysexits.h> defines few exit codes that can be used as a parame-
ter to the exit(3) function. By using these constants the caller of the
process can get a rough estimation about the failure class without look-
ing up the source code.
The successful exit is always indicated by a status of 0, or EX_OK.
Error numbers begin at EX__BASE to reduce the possibility of clashing
with other exit statuses that random programs may already return. The
meaning of the codes is approximately as follows:
EX_USAGE (64) The command was used incorrectly, e.g., with the
wrong number of arguments, a bad flag, a bad syntax
in a parameter, or whatever.
EX_DATAERR (65) The input data was incorrect in some way. This
should only be used for user's data and not system
files.
EX_NOINPUT (66) An input file (not a system file) did not exist or
was not readable. This could also include errors
like ``No message'' to a mailer (if it cared to
catch it).
EX_NOUSER (67) The user specified did not exist. This might be
used for mail addresses or remote logins.
EX_NOHOST (68) The host specified did not exist. This is used in
mail addresses or network requests.
EX_UNAVAILABLE (69) A service is unavailable. This can occur if a sup-
port program or file does not exist. This can also
be used as a catchall message when something you
wanted to do does not work, but you do not know
why.
EX_SOFTWARE (70) An internal software error has been detected. This
should be limited to non-operating system related
errors as possible.
EX_OSERR (71) An operating system error has been detected. This
is intended to be used for such things as ``cannot
fork'', ``cannot create pipe'', or the like. It
includes things like getuid returning a user that
does not exist in the passwd file.
EX_OSFILE (72) Some system file (e.g., /etc/passwd, /var/run/utmp,
etc.) does not exist, cannot be opened, or has some
sort of error (e.g., syntax error).
EX_CANTCREAT (73) A (user specified) output file cannot be created.
EX_IOERR (74) An error occurred while doing I/O on some file.
EX_TEMPFAIL (75) Temporary failure, indicating something that is not
really an error. In sendmail, this means that a
mailer (e.g.) could not create a connection, and
the request should be reattempted later.
EX_PROTOCOL (76) The remote system returned something that was ``not
possible'' during a protocol exchange.
EX_NOPERM (77) You did not have sufficient permission to perform
the operation. This is not intended for file sys-
tem problems, which should use EX_NOINPUT or
EX_CANTCREAT, but rather for higher level permis-
sions.
EX_CONFIG (78) Something was found in an unconfigured or miscon-
figured state.
The numerical values corresponding to the symbolical ones are given in
parenthesis for easy reference.
SEE ALSO
err(3), exit(3), stdlib(3)
HISTORY
The <sysexits.h> header appeared somewhere after 4.3BSD. The manual page
for it appeared in NetBSD 4.0.
AUTHORS
This manual page was written by J"org Wunsch after the comments in
<sysexits.h>.
BUGS
The choice of an appropriate exit value is often ambiguous.
NetBSD 5.0 March 25, 2010 NetBSD 5.0
