NAME    [Toc]    [Back]

       setuid - Set the user ID

SYNOPSIS    [Toc]    [Back]

       #include <unistd.h>

       int setuid(
               uid_t user_id );

       Application  developers  may  want  to specify an #include
       statement for <sys/types.h> before the one for  <unistd.h>
       if  programs  are  being developed for multiple platforms.
       The additional #include statement is not required on Tru64
       UNIX  systems  or  by  ISO  or  XSH  standards, but may be
       required on other vendors' systems that conform  to  these
       standards.

STANDARDS    [Toc]    [Back]

       Interfaces  documented  on  this reference page conform to
       industry standards as follows:

       setuid(): XSH4.0, XSH4.2, XSH5.0

       Refer to the standards(5) reference page for more information
 about industry standards and associated tags.

PARAMETERS    [Toc]    [Back]

       Specifies the new user ID.

DESCRIPTION    [Toc]    [Back]

       The  setuid()  function  sets  the real user ID, effective
       user ID, and the saved set user ID to the user_id  parameter.


       To change the real user ID, the effective user ID, and the
       saved set user ID, the calling process must have superuser
       privilege. If the process does not have appropriate privilege,
 but the user_id parameter is equal to the real  user
       ID  or  the  saved set user ID, the setuid() function sets
       the effective user ID to the user_id parameter.  The  real
       user ID and saved set user ID remain unchanged.

RETURN VALUES    [Toc]    [Back]

       Upon  successful completion, the setuid() function returns
       a value of 0 (zero). Otherwise,  the  function  returns  a
       value of -1 and sets errno to indicate the error.

ERRORS    [Toc]    [Back]

       The  setuid()  function sets errno to the specified values
       for the following conditions: [Tru64 UNIX]  The process is
       attempting an operation that would exceeds a system limit,
       such as the number of tasks or threads allowed for a  user
       ID.   The  value of the user_id parameter is invalid.  The
       process  does  not  have  superuser  privileges,  and  the
       user_id  parameter  does not match the real user ID or the
       saved set user ID.

SEE ALSO    [Toc]    [Back]

       Functions: exec(2), getuid(2), setgid(2), setreuid(2)

       Standards: standards(5)



                                                        setuid(2)