sysexits(3) - NetBSD Manual Pages

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 Jörg Wunsch after the comments in
     <sysexits.h>.


BUGS

     The choice of an appropriate exit value is often ambiguous.

NetBSD 10.99                    March 25, 2010                    NetBSD 10.99