SU(1)                                BSD                                 SU(1)



NAME
     su - substitute user ID temporarily

SYNOPSIS
     su [ -f ] [ - ] [ userid ]

DESCRIPTION
     su permits the temporary substitution of a new user ID.  Before allowing
     this change, however, it demands the password of the specified userid,
     and if it is given, su changes to that userid and invokes the appropriate
     shell without changing the current directory.  The user environment is
     unchanged except for HOME, SHELL, and USER which are taken from the
     account information for the user being substituted (see environ(7)).  The
     new user ID stays in force until the shell exits.

     If you specify no userid, "root" is assumed.  To remind the super users
     of their responsibilities, the shell substitutes a pound sign (#) for its
     usual prompt.

OPTIONS
     -f   Prevent csh(1) from executing the .cshrc file, thus making su start
          up faster.

     -    Simulate a full login.  This option must be followed by a space if
          specified with userid.

NOTES
     You must belong to the group ID "0" to su to "root".

SEE ALSO
     sh(1), csh(1), passwd_override(5)