ref: ea344d4512a08ee0cd09735fe3a57ca44dc4b2b1
dir: /sys/src/libc/9sys/putenv.c/
#include <u.h>
#include <libc.h>
int
putenv(char *name, char *val)
{
char ename[100];
int f, n;
if(name[0]=='\0' || strcmp(name, ".")==0 || strcmp(name, "..")==0 || strchr(name, '/')!=nil
|| strlen(name) >= sizeof(ename)-5){
werrstr("bad env name: %s", name);
return -1;
}
snprint(ename, sizeof(ename), "/env/%s", name);
f = create(ename, OWRITE|OCEXEC, 0664);
if(f < 0)
return -1;
n = strlen(val);
if(write(f, val, n) != n){
close(f);
return -1;
}
close(f);
return 0;
}