[apple/libc.git] / include / sysexits.3

.\"
.\" Copyright (c) 1996 Joerg Wunsch
.\"
.\" All rights reserved.
.\"
.\" Redistribution and use in source and binary forms, with or without
.\" modification, are permitted provided that the following conditions
.\" are met:
.\" 1. Redistributions of source code must retain the above copyright
.\"    notice, this list of conditions and the following disclaimer.
.\" 2. Redistributions in binary form must reproduce the above copyright
.\"    notice, this list of conditions and the following disclaimer in the
.\"    documentation and/or other materials provided with the distribution.
.\"
.\" THIS SOFTWARE IS PROVIDED BY THE DEVELOPERS ``AS IS'' AND ANY EXPRESS OR
.\" IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
.\" OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
.\" IN NO EVENT SHALL THE DEVELOPERS BE LIABLE FOR ANY DIRECT, INDIRECT,
.\" INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
.\" NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
.\" DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
.\" THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
.\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
.\"
.\" $FreeBSD: /repoman/r/ncvs/src/share/man/man3/sysexits.3,v 1.12 2003/09/10 19:24:34 ru Exp $
.\"
.\" "
.Dd March 31, 1996
.Os
.Dt SYSEXITS 3
.Sh NAME
.Nm sysexits
.Nd preferable exit codes for programs
.Sh SYNOPSIS
.In sysexits.h
.Sh DESCRIPTION
According to
.Xr style 9 ,
it is not a good practice to call
.Xr exit 3
with arbitrary values to indicate a failure condition when ending
a program.  Instead, the pre-defined exit codes from
.Nm
should be used, so the caller of the process can get a rough
estimation about the failure class without looking up the source code.
.Pp
The successful exit is always indicated by a status of 0, or
.Sy EX_OK .
Error numbers begin at
.Sy 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:
.Bl -tag -width "EX_UNAVAILABLEXX(XX)"
.It Sy EX_USAGE Pq 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.
.It Sy EX_DATAERR Pq 65
The input data was incorrect in some way.  This should only be used
for user's data and not system files.
.It Sy EX_NOINPUT Pq 66
An input file (not a system file) did not exist or was not readable.
This could also include errors like
.Dq \&No message
to a mailer (if it cared to catch it).
.It Sy EX_NOUSER Pq 67
The user specified did not exist.  This might be used for mail
addresses or remote logins.
.It Sy EX_NOHOST Pq 68
The host specified did not exist.  This is used in mail addresses or
network requests.
.It Sy EX_UNAVAILABLE Pq 69
A service is unavailable.  This can occur if a support program or file
does not exist.  This can also be used as a catchall message when
something you wanted to do doesn't work, but you don't know why.
.It Sy EX_SOFTWARE Pq 70
An internal software error has been detected.  This should be limited
to non-operating system related errors as possible.
.It Sy EX_OSERR Pq 71
An operating system error has been detected.  This is intended to be
used for such things as
.Dq cannot fork ,
.Dq cannot create pipe ,
or the like.  It includes things like getuid returning a user that
does not exist in the passwd file.
.It Sy EX_OSFILE Pq 72
Some system file (e.g.,
.Pa /etc/passwd ,
.Pa /var/run/utmp ,
etc.) does not exist, cannot be opened, or has some sort of error
(e.g., syntax error).
.It Sy EX_CANTCREAT Pq 73
A (user specified) output file cannot be created.
.It Sy EX_IOERR Pq 74
An error occurred while doing I/O on some file.
.It Sy EX_TEMPFAIL Pq 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.
.It Sy EX_PROTOCOL Pq 76
The remote system returned something that was
.Dq not possible
during a protocol exchange.
.It Sy EX_NOPERM Pq 77
You did not have sufficient permission to perform the operation.  This
is not intended for file system problems, which should use
.Sy EX_NOINPUT
or
.Sy EX_CANTCREAT ,
but rather for higher level permissions.
.It Sy EX_CONFIG Pq 78
Something was found in an unconfigured or misconfigured state.
.El
.Pp
The numerical values corresponding to the symbolical ones are given in
parenthesis for easy reference.
.Sh SEE ALSO
.Xr exit 3 ,
.Xr style 9
.Sh HISTORY
The
.Nm
file appeared somewhere after
.Bx 4.3 .
.Sh AUTHORS
This man page has been written by
.An J\(:org Wunsch
after the comments in
.In sysexits.h .
.Sh BUGS
The choice of an appropriate exit value is often ambiguous.
Commit	Line	Data
59e0d9fe A	1	.\"
	2	.\" Copyright (c) 1996 Joerg Wunsch
	3	.\"
	4	.\" All rights reserved.
	5	.\"
	6	.\" Redistribution and use in source and binary forms, with or without
	7	.\" modification, are permitted provided that the following conditions
	8	.\" are met:
	9	.\" 1. Redistributions of source code must retain the above copyright
	10	.\" notice, this list of conditions and the following disclaimer.
	11	.\" 2. Redistributions in binary form must reproduce the above copyright
	12	.\" notice, this list of conditions and the following disclaimer in the
	13	.\" documentation and/or other materials provided with the distribution.
	14	.\"
	15	.\" THIS SOFTWARE IS PROVIDED BY THE DEVELOPERS ``AS IS'' AND ANY EXPRESS OR
	16	.\" IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
	17	.\" OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
	18	.\" IN NO EVENT SHALL THE DEVELOPERS BE LIABLE FOR ANY DIRECT, INDIRECT,
	19	.\" INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
	20	.\" NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
	21	.\" DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
	22	.\" THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
	23	.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
	24	.\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
	25	.\"
	26	.\" $FreeBSD: /repoman/r/ncvs/src/share/man/man3/sysexits.3,v 1.12 2003/09/10 19:24:34 ru Exp $
	27	.\"
	28	.\" "
	29	.Dd March 31, 1996
	30	.Os
	31	.Dt SYSEXITS 3
	32	.Sh NAME
	33	.Nm sysexits
	34	.Nd preferable exit codes for programs
	35	.Sh SYNOPSIS
	36	.In sysexits.h
	37	.Sh DESCRIPTION
	38	According to
	39	.Xr style 9 ,
	40	it is not a good practice to call
	41	.Xr exit 3
	42	with arbitrary values to indicate a failure condition when ending
	43	a program. Instead, the pre-defined exit codes from
	44	.Nm
	45	should be used, so the caller of the process can get a rough
	46	estimation about the failure class without looking up the source code.
	47	.Pp
	48	The successful exit is always indicated by a status of 0, or
	49	.Sy EX_OK .
	50	Error numbers begin at
	51	.Sy EX__BASE
	52	to reduce the possibility of clashing with other exit statuses that
	53	random programs may already return. The meaning of the codes is
	54	approximately as follows:
	55	.Bl -tag -width "EX_UNAVAILABLEXX(XX)"
	56	.It Sy EX_USAGE Pq 64
	57	The command was used incorrectly, e.g., with the wrong number of
	58	arguments, a bad flag, a bad syntax in a parameter, or whatever.
	59	.It Sy EX_DATAERR Pq 65
	60	The input data was incorrect in some way. This should only be used
	61	for user's data and not system files.
	62	.It Sy EX_NOINPUT Pq 66
	63	An input file (not a system file) did not exist or was not readable.
	64	This could also include errors like
65	.Dq \&No message
66	to a mailer (if it cared to catch it).
67	.It Sy EX_NOUSER Pq 67
68	The user specified did not exist. This might be used for mail
69	addresses or remote logins.
70	.It Sy EX_NOHOST Pq 68
71	The host specified did not exist. This is used in mail addresses or
72	network requests.
73	.It Sy EX_UNAVAILABLE Pq 69
74	A service is unavailable. This can occur if a support program or file
75	does not exist. This can also be used as a catchall message when
76	something you wanted to do doesn't work, but you don't know why.
77	.It Sy EX_SOFTWARE Pq 70
78	An internal software error has been detected. This should be limited
79	to non-operating system related errors as possible.
80	.It Sy EX_OSERR Pq 71
81	An operating system error has been detected. This is intended to be
82	used for such things as
83	.Dq cannot fork ,
84	.Dq cannot create pipe ,
85	or the like. It includes things like getuid returning a user that
86	does not exist in the passwd file.
87	.It Sy EX_OSFILE Pq 72
88	Some system file (e.g.,
89	.Pa /etc/passwd ,
90	.Pa /var/run/utmp ,
91	etc.) does not exist, cannot be opened, or has some sort of error
92	(e.g., syntax error).
93	.It Sy EX_CANTCREAT Pq 73
94	A (user specified) output file cannot be created.
95	.It Sy EX_IOERR Pq 74
96	An error occurred while doing I/O on some file.
97	.It Sy EX_TEMPFAIL Pq 75
98	Temporary failure, indicating something that is not really an error.
99	In sendmail, this means that a mailer (e.g.) could not create a
100	connection, and the request should be reattempted later.
101	.It Sy EX_PROTOCOL Pq 76
102	The remote system returned something that was
103	.Dq not possible
104	during a protocol exchange.
105	.It Sy EX_NOPERM Pq 77
106	You did not have sufficient permission to perform the operation. This
107	is not intended for file system problems, which should use
108	.Sy EX_NOINPUT
109	or
110	.Sy EX_CANTCREAT ,
111	but rather for higher level permissions.
112	.It Sy EX_CONFIG Pq 78
113	Something was found in an unconfigured or misconfigured state.
114	.El
115	.Pp
116	The numerical values corresponding to the symbolical ones are given in
117	parenthesis for easy reference.
118	.Sh SEE ALSO
119	.Xr exit 3 ,
120	.Xr style 9
121	.Sh HISTORY
122	The
123	.Nm
124	file appeared somewhere after
125	.Bx 4.3 .
126	.Sh AUTHORS
127	This man page has been written by
128	.An J\(:org Wunsch
129	after the comments in
130	.In sysexits.h .
131	.Sh BUGS
132	The choice of an appropriate exit value is often ambiguous.