GETENV
Section: Linux Programmer's Manual (3)
Updated: 2008-03-17
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NAME
getenv - get an environment variable
SYNOPSIS
#include <stdlib.h>
char *getenv(const char *name);
DESCRIPTION
The
getenv()
function searches the environment list to find the
environment variable
name,
and returns a pointer to the corresponding
value
string.
RETURN VALUE
The
getenv()
function returns a pointer to the value in the
environment, or NULL if there is no match.
CONFORMING TO
SVr4, POSIX.1-2001, 4.3BSD, C89, C99.
NOTES
The strings in the environment list are of the form name=value.
As typically implemented,
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
getenv()
is not required to be reentrant.
The string pointed to by the return value of
getenv()
may be statically allocated,
and can be modified by a subsequent call to
getenv(),
putenv(3),
setenv(3),
or
unsetenv(3).
SEE ALSO
clearenv(3),
putenv(3),
setenv(3),
unsetenv(3),
environ(7)
COLOPHON
This page is part of release 3.22 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/.