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NAME
getusershell, setusershell, endusershell - get permitted user shells
SYNOPSIS
#include <unistd.h>
char *getusershell(void);
void setusershell(void);
void endusershell(void);
Feature Test Macro Requirements for glibc (see feature_test_macros(7)):
getusershell(), setusershell(), endusershell():
_BSD_SOURCE || (_XOPEN_SOURCE && _XOPEN_SOURCE < 500)
DESCRIPTION
The getusershell() function returns the next line from the file /etc/shells, opening the file if
necessary. The line should contain the pathname of a valid user shell. If /etc/shells does not exist or
is unreadable, getusershell() behaves as if /bin/sh and /bin/csh were listed in the file.
The setusershell() function rewinds /etc/shells.
The endusershell() function closes /etc/shells.
RETURN VALUE
The getusershell() function returns a NULL pointer on end-of-file.
FILES
/etc/shells
ATTRIBUTES
Multithreading (see pthreads(7)) The getusershell(), setusershell() and endusershell() functions are not thread-safe.
CONFORMING TO
4.3BSD.
SEE ALSO
shells(5)
COLOPHON
This page is part of release 3.54 of the Linux man-pages project. A description of the project, and
information about reporting bugs, can be found at http://www.kernel.org/doc/man-pages/.
GNU 2013-06-21 GETUSERSHELL(3)