getenv(3C)

NAME

     getenv - return value for environment name

SYNOPSIS

     #include <stdlib.h>

     char *getenv(const char *name);

DESCRIPTION

     The getenv() function searches  the  environment  list  (see
     environ(5))  for a string of the form name=value and, if the
     string is present, returns a pointer to  the  value  in  the
     current environment.

RETURN VALUES

     If successful, getenv() returns a pointer to  the  value  in
     the  current  environment;  otherwise,  it  returns  a  null
     pointer.

USAGE

     The getenv() function can  be  safely  called  from  a  mul-
     tithreaded  application.   Care must be exercised when using
     both getenv() and  putenv(3C) in  a  multithreaded  applica-
     tion.   These  functions  examine and modify the environment
     list, which is shared by all  threads  in  an   application.
     The  system prevents the list from being accessed simultane-
     ously by two  different  threads.   It  does  not,  however,
     prevent two threads from successively accessing the environ-
     ment list using  getenv() or putenv(3C).

ATTRIBUTES

     See attributes(5) for descriptions of the  following  attri-
     butes:

     ____________________________________________________________
    |       ATTRIBUTE TYPE        |       ATTRIBUTE VALUE       |
    |_____________________________|_____________________________|
    | MT-Level                    | Safe                        |
    |_____________________________|_____________________________|

SEE ALSO

     exec(2), putenv(3C), attributes(5), environ(5)