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.\"     @(#)getusershell.3	8.1 (Berkeley) 6/4/93
.\" $FreeBSD$
.\"
.Dd June 4, 1993
.Dt GETUSERSHELL 3
.Os BSD 4.3
.Sh NAME
.Nm getusershell ,
.Nm setusershell ,
.Nm endusershell
.Nd get legal user shells
.Sh SYNOPSIS
.Fd #include <unistd.h>
.Ft char *
.Fn getusershell void
.Ft void
.Fn setusershell void
.Ft void
.Fn endusershell void
.Sh DESCRIPTION
The
.Fn getusershell
function
returns a pointer to a legal user shell as defined by the
system manager in the file 
.Pa /etc/shells .
If 
.Pa /etc/shells
is unreadable or does not exist,
.Fn getusershell
behaves as if
.Pa /bin/sh
and
.Pa /bin/csh
were listed in the file.
.Pp
The
.Fn getusershell
function
reads the next
line (opening the file if necessary);
.Fn setusershell
rewinds the file;
.Fn endusershell
closes it.
.Sh FILES
.Bl -tag -width /etc/shells -compact
.It Pa /etc/shells
.El
.Sh DIAGNOSTICS
The routine
.Fn getusershell
returns a null pointer (0) on
.Dv EOF .
.Sh SEE ALSO
.Xr shells 5
.Sh HISTORY
The
.Fn getusershell
function appeared in 
.Bx 4.3 .
.Sh BUGS
The
.Fn getusershell
function leaves its result in an internal static object and returns
a pointer to that object. Subsequent calls to
.Fn getusershell
will modify the same object.