xref: /freebsd/lib/libutil/getlocalbase.3 (revision 4543ef516683042d46f3bd3bb8a4f3f746e00499)
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5.\" Copyright 2020 Stefan Eßer
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28.Dd July 11, 2023
29.Dt GETLOCALBASE 3
30.Os
31.Sh NAME
32.Nm getlocalbase
33.Nd "return the path to the local software directory"
34.Sh LIBRARY
35.Lb libutil
36.Sh SYNOPSIS
37.In libutil.h
38.Ft const char*
39.Fn getlocalbase "void"
40.Sh DESCRIPTION
41The
42.Fn getlocalbase
43function returns the path to the local software base directory.
44Normally this is the
45.Pa /usr/local
46directory.
47First the
48.Ev LOCALBASE
49environment variable is checked.
50If that does not exist then the
51.Va user.localbase
52sysctl is checked.
53If that also does not exist then the value of the
54.Dv LOCALBASE_PATH
55compile-time variable is used.
56If that is undefined then the system default,
57.Pa _PATH_LOCALBASE
58is used.
59.Pp
60The contents of the string returned by the
61.Fn getlocalbase
62function shall not be modified.
63.Sh IMPLEMENTATION NOTES
64Calls to
65.Fn getlocalbase
66will perform a setugid check on the running binary before checking the
67environment.
68.Pp
69The address returned by
70.Fn getlocalbase
71will point into the executing processes environment if it is the result of
72.Fn getenv "LOCALBASE" ,
73to a static buffer if it is the result of
74.Fn sysctl "user.localbase" ,
75and to a constant string if the compiled in default value is returned.
76.Pp
77The same value will be returned on successive calls during the run-time
78of the program, ignoring any changes to the environment variable or the
79sysctl value that might have been made.
80.Pp
81The
82.Fn getlocalbase
83function can be compiled with a non-default value of LOCALBASE_CTL_LEN.
84A value of 0 will disable fetching of the sysctl value, a value less than
85MAXPATHLEN will put a limit on the maximum string length supported for
86this sysctl value.
87If built with a non-default value of LOCALBASE_CTL_LEN, a value of the
88user.localbase sysctl variable longer than this value will make
89.Fn getlocalbase
90return a valid string that is not a valid path prefix in any filesystem.
91.Sh RETURN VALUES
92The
93.Fn getlocalbase
94function returns a pointer to a string, whose length may exceed MAXPATHLEN,
95if it has been obtained from the environment.
96.Sh ENVIRONMENT
97The
98.Fn getlocalbase
99library function retrieves the
100.Ev LOCALBASE
101environment variable.
102.Sh ERRORS
103The
104.Fn getlocalbase
105function always succeeds and returns a valid pointer to a string.
106.Sh SEE ALSO
107.Xr env 1 ,
108.Xr src.conf 5 ,
109.Xr sysctl 8
110.Sh HISTORY
111The
112.Nm
113library function first appeared in
114.Fx 13.0 .
115.Sh AUTHORS
116.An -nosplit
117This
118manual page was written by
119.An Scott Long Aq Mt scottl@FreeBSD.org
120and
121.An Stefan Eßer Aq Mt se@FreeBSD.org .
122