Name
getenv
Synopsis
Obtains the string value of a specified environment variable
#include <stdlib.h> char *getenv
( const char *name
);
The getenv()
function
searches the environment variables at runtime for an entry with the
specified name, and returns a pointer to the variable’s value. If
there is no environment variable with the specified name, getenv()
returns a null pointer.
Your program must not modify the string addressed by the
pointer returned, and the string at that address may be replaced by
subsequent calls to getenv()
.
Furthermore, C itself does not define a function to set or modify
environment variables, or any list of variable names that you can
expect to exist; these features, if available at all, are
system-specific.
Example
#define MAXPATH 1024;
char sPath[MAXPATH] = "";
char *pTmp;
if (( pTmp =getenv
( "PATH" )) != NULL )
strncpy( sPath, pTmp, MAXPATH − 1 ); // Save a copy for our use.
else
fprintf( stderr, "No PATH variable set.\n") ;
See Also
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