NAME
setenv - change or add an environment variable
SYNOPSIS
#include <stdlib.h>
int setenv(const char *name, const char *value, int overwrite
void unsetenv(const char *name));
DESCRIPTION
The setenv() function adds the variable name to the environ-
ment with the value value, if name does not already exist.
If name does exist in the environment, then its value is
changed to value if overwrite is non-zero; if overwrite is
zero, then the value of name is not changed.
The unsetenv() function deletes the variable name from the
environment.
RETURN VALUE
The setenv() function returns zero on success, or -1 if
there was insufficient space in the environment.
CONFORMING TO
BSD 4.3
SEE ALSO
getenv(3), putenv(3), environ(5)