sysexits.h(3head)

NAME
sysexits.h - exit codes for programs

LIBRARY
Standard C library (libc)

SYNOPSIS
#include <sysexits.h>
#define EX_OK | 0 | /* | successful termination */
#define EX__BASE | 64 | /* | base value for error messages */
#define EX_USAGE | 64 | /* | command line usage error */
#define EX_DATAERR | 65 | /* | data format error */
#define EX_NOINPUT | 66 | /* | cannot open input */
#define EX_NOUSER | 67 | /* | addressee unknown */
#define EX_NOHOST | 68 | /* | host name unknown */
#define EX_UNAVAILABLE | 69 | /* | service unavailable */
#define EX_SOFTWARE | 70 | /* | internal software error */
#define EX_OSERR | 71 | /* | system error (e.g., can't fork) */
#define EX_OSFILE | 72 | /* | critical OS file missing */
#define EX_CANTCREAT | 73 | /* | can't create (user) output file */
#define EX_IOERR | 74 | /* | input/output error */
#define EX_TEMPFAIL | 75 | /* | temp failure; user is invited to retry */
#define EX_PROTOCOL | 76 | /* | remote error in protocol */
#define EX_NOPERM | 77 | /* | permission denied */
#define EX_CONFIG | 78 | /* | configuration error */
#define EX__MAX | ... | /* | maximum listed value */

DESCRIPTION
A few programs exit with the following error codes.

The successful exit is always indicated by a status of 0, or EX_OK (equivalent to EXIT_SUCCESS from <stdlib.h>). 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 code is approximately as follows:

EX_USAGE
    The command was used incorrectly, e.g., with the wrong number of arguments, a bad flag, bad syntax in a parameter, or whatever.

EX_DATAERR
    The input data was incorrect in some way. This should only be used for user's data and not system files.

EX_NOINPUT
    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
    The user specified did not exist. This might be used for mail addresses or remote logins.

EX_NOHOST
    The host specified did not exist. This is used in mail addresses or network requests.

EX_UNAVAILABLE
    A service is unavailable. This can occur if a support program or file does not exist. This can also be used as a catch-all message when something you wanted to do doesn't work, but you don't know why.

EX_SOFTWARE
    An internal software error has been detected. This should be limited to non-operating system related errors if possible.

EX_OSERR
    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(2) returning a user that does not exist in the passwd(5) file.

EX_OSFILE
    Some system file (e.g., /etc/passwd, /etc/utmp, etc.) does not exist, cannot be opened, or has some sort of error (e.g., syntax error).

EX_CANTCREAT
    A (user specified) output file cannot be created.

EX_IOERR
    An error occurred while doing I/O on some file.

EX_TEMPFAIL
    Temporary failure, indicating something that is not really an error. For example that a mailer could not create a connection, and the request should be reattempted later.

EX_PROTOCOL
    The remote system returned something that was "not possible" during a protocol exchange.

EX_OSFILE
    You did not have sufficient permission to perform the operation. This is not intended for file system problems, which should use EX_NOINPUT or EX_CANTCREAT, but rather for higher level permissions.

EX_CONFIG
    Something was found in an unconfigured or misconfigured state.

The numerical values corresponding to the symbolical ones are given in parenthesis for easy reference.

STANDARDS
BSD.

HISTORY
The <sysexits.h> file appeared in 4.0BSD for use by the deliverymail utility, later renamed to sendmail(8).

CAVEATS
The choice of an appropriate exit value is often ambiguous.

SEE ALSO
err(3), error(3), exit(3)