passwdbyuid
passwdbyuid is a function or utility used in Unix-like systems to retrieve a user account entry from the system's password database by user ID (UID). It typically returns a structured record containing fields such as the login name, password placeholder, UID, GID, user information (GEcos), home directory, and login shell. In POSIX systems the standard API that serves a similar purpose is getpwuid, with a reentrant variant getpwuid_r; passwdbyuid may be a wrapper or a library-specific alias implementing similar semantics.
Usage and behavior: A caller supplies a UID to passwdbyuid. On success, the function returns a pointer
Security considerations: In modern systems the actual password hash is not stored in the public password database
Availability and compatibility: passwdbyuid is not a standard POSIX function. In environments where it is not
See also: getpwuid, getpwuid_r, /etc/passwd, /etc/shadow, UID, GID.