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NAME | LIBRARY | SYNOPSIS | DESCRIPTION | STANDARDS | HISTORY | CAVEATS | SEE ALSO |
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sysexits.h(3head) sysexits.h(3head)
sysexits.h - exit codes for programs
Standard C library (libc)
#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 */
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.
BSD.
The <sysexits.h> file appeared in 4.0BSD for use by the
deliverymail utility, later renamed to sendmail(8).
The choice of an appropriate exit value is often ambiguous.
err(3), error(3), exit(3)
Linux man-pages (unreleased) (date) sysexits.h(3head)
Pages that refer to this page: EXIT_SUCCESS(3const)
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HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. |
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