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NAME | SYNOPSIS | DESCRIPTION | RETURN VALUE | CONFORMING TO | NOTES | SEE ALSO | COLOPHON


GETENV(3)                     Linux Programmer's Manual                     GETENV(3)

NAME         top

       getenv - get an environment variable

SYNOPSIS         top

       #include <stdlib.h>

       char *getenv(const char *name);

DESCRIPTION         top

       The getenv() function searches the environment list to find the environment
       variable name, and returns a pointer to the corresponding value string.

RETURN VALUE         top

       The getenv() function returns a pointer to the value in the environment, or
       NULL if there is no match.

CONFORMING TO         top

       SVr4, POSIX.1-2001, 4.3BSD, C89, C99.

NOTES         top

       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         top

       clearenv(3), putenv(3), setenv(3), unsetenv(3), environ(7)

COLOPHON         top

       This page is part of release 3.23 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                                   2008-03-17                            GETENV(3)