C: Get uid by loginname

#include <sys/types.h>
#include <pwd.h>
uid_t getuid_by_loginname(const char *name)
{
 struct passwd *pwd;
 if(name) {
  pwd = getpwnam(name); /* don't free, see getpwnam() for details */
  if(pwd)
   return pwd->pw_uid;
 }
 
 return (uid_t)-1;
}