GETPW(3) Library Functions Manual GETPW(3)
getpw - get name from uid
getpw() is obsoleted by getpwent(3V).
getpw() searches the password file for the (numerical) uid, and fills
in buf with the corresponding line; it returns non-zero if uid could
not be found. The line is null-terminated.
Non-zero return on error.
6 October 1987 GETPW(3)