man pages section 1: User Commands
    
U
 
 u370 -- get processor type truth value ( Index Term Link )
 
 u3b -- get processor type truth value ( Index Term Link )
 
 u3b2 -- get processor type truth value ( Index Term Link )
 
 u3b5 -- get processor type truth value ( Index Term Link )
 
 u3b15 -- get processor type truth value ( Index Term Link )
 
 ucblinks -- adds /dev entries to give SunOS 4.x compatible names to SunOS 5.x devices ( Index Term Link )
 
 ul -- underline text ( Index Term Link )
 
 ulimit -- set or get limitations on the system resources available to the current shell and its descendents ( Index Term Link )
 
 umask -- shell built-in function to restrict read/write/execute permissions ( Index Term Link )
 
 unalias -- shell built-in functions to create your own pseudonym or shorthand for a command or series of commands ( Index Term Link )
 
 uname -- print name of current system ( Index Term Link )
 
 unbind the reference from an FNS name -- fnunbind ( Index Term Link )
 
 uncompress -- uncompress files ( Index Term Link )
 
 underline text -- ul ( Index Term Link )
 
 unexpand -- unexpand SPACE characters to TAB characters ( Index Term Link )
 
 unhash -- shell built-in functions to evaluate the internal hash table of the contents of directories ( Index Term Link )
 
 unifdef -- resolve and remove ifdef'ed lines from C program source ( Index Term Link )
 
 uniq -- report or filter out repeated lines in a file ( Index Term Link )
 
 units -- converts quantities expressed in standard scales to other scales ( Index Term Link )
 
 UNIX, convert text file from DOS format to ISO format -- dos2unix ( Index Term Link )
 
 unix2dos -- convert text file from ISO format to DOS format ( Index Term Link )
 
 UNIX-to-UNIX commands
  uucp -- uucp ( Index Term Link )
  uulog -- uucp ( Index Term Link )
  uuname -- uucp ( Index Term Link )
 
 unlimit -- set or get limitations on the system resources available to the current shell and its descendents ( Index Term Link )
 
 unpack -- expand compressed files ( Index Term Link )
 
 unset -- shell built-in functions to determine the characteristics for environmental variables of the current shell and its descendents ( Index Term Link )
 
 unsetenv -- shell built-in functions to determine the characteristics for environmental variables of the current shell and its descendents ( Index Term Link )
 
 update and examine attributes associated with FNS named object -- fnattr ( Index Term Link )
 
 update groups of programs -- sysV-make ( Index Term Link )
 
 update last modified date of file -- touch ( Index Term Link )
 
 update programs -- make ( Index Term Link )
 
 uptime -- show how long the system has been up ( Index Term Link )
 
 user ID, change user IDs of files -- chown ( Index Term Link )
 
 user IDs
  display a list of all valid user names -- dispuid ( Index Term Link )
  prompts for user ID -- ckuid ( Index Term Link )
  provides error message for user ID -- erruid ( Index Term Link )
  provides help message for user ID -- helpuid ( Index Term Link )
  validates user ID -- valuid ( Index Term Link )
 
 users
  display effective name -- whoami ( Index Term Link )
  display group membership -- groups ( Index Term Link )
  display information about local and remote users -- finger ( Index Term Link )
  get the name of the user running the process -- logname ( Index Term Link )
  list user login information -- listusers ( Index Term Link )
  talk to another user -- talk ( Index Term Link )
  who is logged in, and what are they doing -- w ( Index Term Link )
  who is logged in on local machines -- rwho ( Index Term Link )
  who is logged in on remote machines -- rusers ( Index Term Link )
  who is on the system -- who ( Index Term Link )
  write to another user -- write ( Index Term Link )
 
 users, network, Internet user name directory service -- whois ( Index Term Link )
 
 users -- display users on system ( Index Term Link )
 
 uucp -- UNIX-to-UNIX copy ( Index Term Link )
 
 uucp
  log -- uulog ( Index Term Link )
  uucp status inquiry -- uustat ( Index Term Link )
 
 uudecode -- decode binary file ( Index Term Link )
 
 uuencode -- encode binary file ( Index Term Link )
 
 uuglist -- print list of service grades available ( Index Term Link )
 
 uulog -- UUCP log ( Index Term Link )
 
 uuname -- UUCP list of names ( Index Term Link )
 
 uustat -- uucp status inquiry ( Index Term Link )
 
 uux -- system to system command execution ( Index Term Link )