getenv
---look up environment variable#include <stdlib.h> char *getenv(const char *name);Description
getenv
searches the list of environment variable names and values
(using the global pointer `char **environ
') for a variable whose
name matches the string at name. If a variable name matches,
getenv
returns a pointer to the associated value.
Returns
A pointer to the (string) value of the environment variable, or
NULL
if there is no such environment variable.
Portability
getenv
is ANSI, but the rules for properly forming names of environment
variables vary from one system to another.
getenv
requires a global pointer environ
.