NAME

       setuid - run a command with a different uid.

SYNOPSIS

       setuid username|uid   command [ args ]

DESCRIPTION

       Setuid changes user id, then executes the specified command.  Unlike some versions of su(1), this program
       doesn't ever ask for a password when executed with effective uid=root.  This program doesn't  change  the
       environment;  it only changes the uid and then uses execvp() to find the command in the path, and execute
       it.  (If the command is a script, execvp() passes the command name to /bin/sh for processing.)

       For example,
              setuid  some_user  $SHELL
       can be used to start a shell running as another user.

       Setuid is useful inside scripts that are being run by a setuid-root user — such as a script invoked  with
       super,  so that the script can execute some commands using the uid of the original user, instead of root.
       This allows unsafe commands (such as editors and pagers) to be used in a non-root  mode  inside  a  super
       script.   For  example,  an operator with permission to modify a certain protected_file could use a super
       command that simply does:
              cp protected_file temp_file
              setuid $ORIG_USER ${EDITOR:-/bin/vi} temp_file
              cp temp_file protected_file
       (Note: don't use this example directly.  If the temp_file can somehow be replaced  by  another  user,  as
       might  be  the  case  if  it's  kept in a temporary directory, there will be a race condition in the time
       between editing the temporary file and copying it back to the protected file.)

AUTHOR

       Will Deich

                                                      local                                            SETUID(1)