/* | |
* unsetenv.c | |
*/ | |
#include <errno.h> | |
#include <stdlib.h> | |
#include <string.h> | |
#include <unistd.h> | |
int unsetenv(const char *name) | |
{ | |
size_t len; | |
char **p, *q; | |
const char *z; | |
if ( !name || !name[0] ) { | |
errno = EINVAL; | |
return -1; | |
} | |
len = 0; | |
for ( z = name ; *z ; z++ ) { | |
len++; | |
if ( *z == '=' ) { | |
errno = EINVAL; | |
return -1; | |
} | |
} | |
for ( p = environ ; (q = *p) ; p++ ) { | |
if ( !strncmp(name,q,len) && q[len] == '=' ) | |
break; | |
} | |
for ( ; (q = *p) ; p++ ) { | |
p[0] = p[1]; | |
} | |
return 0; | |
} |