man pages section 4: File Formats
    
U
 
 ufsdump — incremental dump format ( Index Term Link )
 
 updaters — configuration file for NIS updating ( Index Term Link )
 
 user-preference variables files for AT&T FACE — environ ( Index Term Link )
 
 daemon parameters for NFS — nfs ( Index Term Link )
 
 utmp — utmp and wtmp database entry formats ( Index Term Link )
 
 utmp and wtmp database entry formats — utmp ( Index Term Link )
 
 utmp and wtmp database entry formats — wtmp ( Index Term Link )
 
 utmpx — utmpx and wtmpx database entry formats ( Index Term Link )
 
 utmpx and wtmpx database entry formats — utmpx ( Index Term Link )
 
 utmpx and wtmpx database entry formats — wtmpx ( Index Term Link )