+++ /dev/null
-.\" Copyright 1993 David Metcalfe (david@prism.demon.co.uk)
-.\" and Copyright (C) 2007, 2012 Michael Kerrisk <mtk.manpages@gmail.com>
-.\"
-.\" %%%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-.\" manual page may be incorrect or out-of-date.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
-.\" professionally.
-.\"
-.\" Formatted or processed versions of this manual, if unaccompanied by
-.\" the source, must acknowledge the copyright and authors of this work.
-.\" %%%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 19:30:29 1993 by Rik Faith (faith@cs.unc.edu)
-.\" Modified Fri Feb 14 21:47:50 1997 by Andries Brouwer (aeb@cwi.nl)
-.\"
-.TH GETENV 3 2012-08-14 "GNU" "Linux Programmer's Manual"
-.SH NAME
-getenv, secure_getenv \- get an environment variable
-.SH SYNOPSIS
-.nf
-.B #include <stdlib.h>
-.sp
-.BI "char *getenv(const char *" name );
-
-.BI "char *secure_getenv(const char *" name );
-.fi
-.sp
-.in -4n
-Feature Test Macro Requirements for glibc (see
-.BR feature_test_macros (7)):
-.in
-.sp
-.BR secure_getenv ():
-_GNU_SOURCE
-.SH DESCRIPTION
-The
-.BR getenv ()
-function searches the environment list to find the
-environment variable
-.IR name ,
-and returns a pointer to the corresponding
-.I value
-string.
-
-The GNU-specific
-.BR secure_getenv ()
-function is just like
-.BR getenv ()
-except that it returns NULL in cases where "secure execution" is required.
-Secure execution is required if one of the following conditions
-was true when the program run by the calling process was loaded:
-.IP * 3
-the process's effective user ID did not match its real user ID or
-the process's effective group ID did not match its real group ID
-(typically this is the result of executing a set-user-ID or
-set-group-ID program);
-.IP *
-the effective capability bit was set on the executable file; or
-.IP *
-the process has a nonempty permitted capability set.
-.PP
-Secure execution may also required if triggered
-by some Linux security modules.
-
-The
-.BR secure_getenv ()
-function is intended for use in general-purpose libraries
-to avoid vulnerabilities that could occur if
-set-user-ID or set-group-ID programs accidentally
-trusted the environment.
-.SH RETURN VALUE
-The
-.BR getenv ()
-function returns a pointer to the value in the
-environment, or NULL if there is no match.
-.SH VERSIONS
-.BR secure_getenv ()
-first appeared in glibc 2.17.
-.SH CONFORMING TO
-.BR getenv ():
-SVr4, POSIX.1-2001, 4.3BSD, C89, C99.
-
-.BR secure_getenv ()
-is a GNU extension.
-.SH NOTES
-The strings in the environment list are of the form \fIname=value\fP.
-
-As typically implemented,
-.BR getenv ()
-returns a pointer to a string within the environment list.
-The caller must take care not to modify this string,
-since that would change the environment of the process.
-
-The implementation of
-.BR getenv ()
-is not required to be reentrant.
-The string pointed to by the return value of
-.BR getenv ()
-may be statically allocated,
-and can be modified by a subsequent call to
-.BR getenv (),
-.BR putenv (3),
-.BR setenv (3),
-or
-.BR unsetenv (3).
-
-The "secure execution" mode of
-.BR secure_getenv ()
-is controlled by the
-.B AT_SECURE
-flag contained in the auxiliary vector passed from the kernel to user space.
-.SH SEE ALSO
-.BR clearenv (3),
-.BR getauxval (3),
-.BR putenv (3),
-.BR setenv (3),
-.BR unsetenv (3),
-.BR capabilities (7),
-.BR environ (7)
-.SH COLOPHON
-This page is part of release 3.79 of the Linux
-.I man-pages
-project.
-A description of the project,
-information about reporting bugs,
-and the latest version of this page,
-can be found at
-\%http://www.kernel.org/doc/man\-pages/.
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