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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

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       description of the project, and information about reporting  bugs,  can
       be found at http://www.kernel.org/doc/man-pages/.