xref: /freebsd/lib/libutil/getlocalbase.3 (revision 2b8331622f0b212cf3bb4fc4914a501e5321d506)
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4.\" Copyright 2020 Scott Long
5.\" Copyright 2020 Stefan Eßer
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28.\" $FreeBSD$
29.\"
30.Dd November 25, 2020
31.Dt GETLOCALBASE 3
32.Os
33.Sh NAME
34.Nm getlocalbase
35.Nd "return the path to the local software directory"
36.Sh LIBRARY
37.Lb libutil
38.Sh SYNOPSIS
39.In libutil.h
40.Ft const char*
41.Fn getlocalbase "void"
42.Sh DESCRIPTION
43The
44.Fn getlocalbase
45function returns the path to the local software base directory.
46Normally this is the
47.Pa /usr/local
48directory.
49First the
50.Ev LOCALBASE
51environment variable is checked.
52If that does not exist then the
53.Va user.localbase
54sysctl is checked.
55If that also does not exist then the value of the
56.Dv _PATH_LOCALBASE
57compile-time variable is used.
58If that is undefined then the default of
59.Pa /usr/local
60is used.
61.Pp
62The contents of the string returned by the
63.Fn getlocalbase
64function shall not be modified.
65.Sh IMPLEMENTATION NOTES
66Calls to
67.Fn getlocalbase
68will perform a setugid check on the running binary before checking the
69environment.
70.Pp
71The address returned by
72.Fn getlocalbase
73will point into the executing processes environment if it is the result of
74.Fn getenv "LOCALBASE" ,
75to a static buffer if it is the result of
76.Fn sysctl "user.localbase" ,
77and to a constant string if the compiled in default value is returned.
78.Pp
79The same value will be returned on successive calls during the run-time
80of the program, ignoring any changes to the environment variable or the
81sysctl value that might have been made.
82.Pp
83The
84.Fn getlocalbase
85function can be compiled with a non-default value of LOCALBASE_CTL_LEN.
86A value of 0 will disable fetching of the sysctl value, a value less than
87MAXPATHLEN will put a limit on the maximum string length supported for
88this sysctl value.
89If built with a non-default value of LOCALBASE_CTL_LEN, a value of the
90user.localbase sysctl variable longer than this value will make
91.Fn getlocalbase
92return a valid string that is not a valid path prefix in any filesystem.
93.Sh RETURN VALUES
94The
95.Fn getlocalbase
96function returns a pointer to a string, whose length may exceed MAXPATHLEN,
97if it has been obtained from the environment.
98.Sh ENVIRONMENT
99The
100.Fn getlocalbase
101library function retrieves the
102.Ev LOCALBASE
103environment variable.
104.Sh ERRORS
105The
106.Fn getlocalbase
107function always succeeds and returns a valid pointer to a string.
108.Sh SEE ALSO
109.Xr env 1 ,
110.Xr src.conf 5 ,
111.Xr sysctl 8
112.Sh HISTORY
113The
114.Nm
115library function first appeared in
116.Fx 13.0 .
117.Sh AUTHORS
118This
119manual page was written by
120.An Scott Long Aq Mt scottl@FreeBSD.org and Stefan Eßer Aq Mt se@FreeBSD.org .
121