2 .\" Copyright (c) 1996 Joerg Wunsch
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32 .Nd preferable exit codes for programs
38 it is not a good practice to call
40 with arbitrary values to indicate a failure condition when ending
42 Instead, the pre-defined exit codes from
44 should be used, so the caller of the process can get a rough
45 estimation about the failure class without looking up the source code.
47 The successful exit is always indicated by a status of 0, or
49 Error numbers begin at
51 to reduce the possibility of clashing with other exit statuses that
52 random programs may already return.
53 The meaning of the codes is
54 approximately as follows:
55 .Bl -tag -width "EX_UNAVAILABLEXX(XX)"
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.
61 This should only be used
62 for user's data and not system files.
63 .It Sy EX_NOINPUT Pq 66
64 An input file (not a system file) did not exist or was not readable.
65 This could also include errors like
67 to a mailer (if it cared to catch it).
68 .It Sy EX_NOUSER Pq 67
69 The user specified did not exist.
70 This might be used for mail
71 addresses or remote logins.
72 .It Sy EX_NOHOST Pq 68
73 The host specified did not exist.
74 This is used in mail addresses or
76 .It Sy EX_UNAVAILABLE Pq 69
77 A service is unavailable.
78 This can occur if a support program or file
80 This can also be used as a catchall message when
81 something you wanted to do does not work, but you do not know why.
82 .It Sy EX_SOFTWARE Pq 70
83 An internal software error has been detected.
84 This should be limited
85 to non-operating system related errors as possible.
87 An operating system error has been detected.
88 This is intended to be
89 used for such things as
91 .Dq cannot create pipe ,
93 It includes things like getuid returning a user that
94 does not exist in the passwd file.
95 .It Sy EX_OSFILE Pq 72
96 Some system file (e.g.,
98 .Pa /var/run/utx.active ,
99 etc.) does not exist, cannot be opened, or has some sort of error
100 (e.g., syntax error).
101 .It Sy EX_CANTCREAT Pq 73
102 A (user specified) output file cannot be created.
103 .It Sy EX_IOERR Pq 74
104 An error occurred while doing I/O on some file.
105 .It Sy EX_TEMPFAIL Pq 75
106 Temporary failure, indicating something that is not really an error.
107 In sendmail, this means that a mailer (e.g.) could not create a
108 connection, and the request should be reattempted later.
109 .It Sy EX_PROTOCOL Pq 76
110 The remote system returned something that was
112 during a protocol exchange.
113 .It Sy EX_NOPERM Pq 77
114 You did not have sufficient permission to perform the operation.
116 is not intended for file system problems, which should use
120 but rather for higher level permissions.
121 .It Sy EX_CONFIG Pq 78
122 Something was found in an unconfigured or misconfigured state.
125 The numerical values corresponding to the symbolical ones are given in
126 parenthesis for easy reference.
134 file appeared somewhere after
137 This manual page was written by
139 after the comments in
142 The choice of an appropriate exit value is often ambiguous.