xref: /freebsd/lib/libc/gen/getusershell.3 (revision ce834215a70ff69e7e222827437116eee2f9ac6f)
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32.\"     @(#)getusershell.3	8.1 (Berkeley) 6/4/93
33.\"
34.Dd June 4, 1993
35.Dt GETUSERSHELL 3
36.Os BSD 4.3
37.Sh NAME
38.Nm getusershell ,
39.Nm setusershell ,
40.Nm endusershell
41.Nd get legal user shells
42.Sh SYNOPSIS
43.Fd #include <unistd.h>
44.Ft char *
45.Fn getusershell void
46.Ft void
47.Fn setusershell void
48.Ft void
49.Fn endusershell void
50.Sh DESCRIPTION
51The
52.Fn getusershell
53function
54returns a pointer to a legal user shell as defined by the
55system manager in the file
56.Pa /etc/shells .
57If
58.Pa /etc/shells
59is unreadable or does not exist,
60.Fn getusershell
61behaves as if
62.Pa /bin/sh
63and
64.Pa /bin/csh
65were listed in the file.
66.Pp
67The
68.Fn getusershell
69function
70reads the next
71line (opening the file if necessary);
72.Fn setusershell
73rewinds the file;
74.Fn endusershell
75closes it.
76.Sh FILES
77.Bl -tag -width /etc/shells -compact
78.It Pa /etc/shells
79.El
80.Sh DIAGNOSTICS
81The routine
82.Fn getusershell
83returns a null pointer (0) on
84.Dv EOF .
85.Sh SEE ALSO
86.Xr shells 5
87.Sh HISTORY
88The
89.Fn getusershell
90function appeared in
91.Bx 4.3 .
92.Sh BUGS
93The
94.Fn getusershell
95function leaves its result in an internal static object and returns
96a pointer to that object. Subsequent calls to
97.Fn getusershell
98will modify the same object.
99