GETUSERSHELL(3) Linux Programmer's Manual GETUSERSHELL(3)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():
Since glibc 2.21:
_DEFAULT_SOURCE
In glibc 2.19 and 2.20:
_DEFAULT_SOURCE || (_XOPEN_SOURCE && _XOPEN_SOURCE < 500)
Up to and including glibc 2.19:
_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 NULL on end-of-file.
FILES
/etc/shells
ATTRIBUTES
For an explanation of the terms used in this section, see
attributes(7).
┌────────────────────────────────┬───────────────┬───────────┐
│Interface │ Attribute │ Value │
├────────────────────────────────┼───────────────┼───────────┤
│getusershell(), setusershell(), │ Thread safety │ MT-Unsafe │
│endusershell() │ │ │
└────────────────────────────────┴───────────────┴───────────┘
CONFORMING TO
4.3BSD.
SEE ALSOshells(5)COLOPHON
This page is part of release 4.14 of the Linux man-pages project. A
description of the project, information about reporting bugs, and the
latest version of this page, can be found at
https://www.kernel.org/doc/man-pages/.
GNU 2016-03-15 GETUSERSHELL(3)
