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 environment 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)