| .\" Copyright 1993 David Metcalfe (david@prism.demon.co.uk) |
| .\" |
| .\" %%%LICENSE_START(VERBATIM) |
| .\" Permission is granted to make and distribute verbatim copies of this |
| .\" manual provided the copyright notice and this permission notice are |
| .\" preserved on all copies. |
| .\" |
| .\" Permission is granted to copy and distribute modified versions of this |
| .\" manual under the conditions for verbatim copying, provided that the |
| .\" entire resulting derived work is distributed under the terms of a |
| .\" permission notice identical to this one. |
| .\" |
| .\" Since the Linux kernel and libraries are constantly changing, this |
| .\" manual page may be incorrect or out-of-date. The author(s) assume no |
| .\" responsibility for errors or omissions, or for damages resulting from |
| .\" the use of the information contained herein. The author(s) may not |
| .\" have taken the same level of care in the production of this manual, |
| .\" which is licensed free of charge, as they might when working |
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| .\" Formatted or processed versions of this manual, if unaccompanied by |
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| .\" %%%LICENSE_END |
| .\" |
| .\" References consulted: |
| .\" Linux libc source code |
| .\" Lewine's _POSIX Programmer's Guide_ (O'Reilly & Associates, 1991) |
| .\" 386BSD man pages |
| .\" Modified Sat Jul 24 19:17:53 1993 by Rik Faith (faith@cs.unc.edu) |
| .TH GETUSERSHELL 3 2021-03-22 "GNU" "Linux Programmer's Manual" |
| .SH NAME |
| getusershell, setusershell, endusershell \- get permitted user shells |
| .SH SYNOPSIS |
| .nf |
| .B #include <unistd.h> |
| .PP |
| .B char *getusershell(void); |
| .B void setusershell(void); |
| .B void endusershell(void); |
| .fi |
| .PP |
| .RS -4 |
| Feature Test Macro Requirements for glibc (see |
| .BR feature_test_macros (7)): |
| .RE |
| .PP |
| .BR getusershell (), |
| .BR setusershell (), |
| .BR endusershell (): |
| .nf |
| Since glibc 2.21: |
| .\" commit 266865c0e7b79d4196e2cc393693463f03c90bd8 |
| _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) |
| .fi |
| .SH DESCRIPTION |
| The |
| .BR getusershell () |
| function returns the next line from the file |
| .IR /etc/shells , |
| opening the file if necessary. |
| The line should contain |
| the pathname of a valid user shell. |
| If |
| .I /etc/shells |
| does not exist or |
| is unreadable, |
| .BR getusershell () |
| behaves as if |
| .I /bin/sh |
| and |
| .I /bin/csh |
| were listed in the file. |
| .PP |
| The |
| .BR setusershell () |
| function rewinds |
| .IR /etc/shells . |
| .PP |
| The |
| .BR endusershell () |
| function closes |
| .IR /etc/shells . |
| .SH RETURN VALUE |
| The |
| .BR getusershell () |
| function returns NULL on end-of-file. |
| .SH FILES |
| .I /etc/shells |
| .SH ATTRIBUTES |
| For an explanation of the terms used in this section, see |
| .BR attributes (7). |
| .ad l |
| .nh |
| .TS |
| allbox; |
| lbx lb lb |
| l l l. |
| Interface Attribute Value |
| T{ |
| .BR getusershell (), |
| .BR setusershell (), |
| .BR endusershell () |
| T} Thread safety MT-Unsafe |
| .TE |
| .hy |
| .ad |
| .sp 1 |
| .SH CONFORMING TO |
| 4.3BSD. |
| .SH SEE ALSO |
| .BR shells (5) |