usrinfo

Purpose

     Gets and  sets user  information about  the owner  of the
     calling process.

Syntax

     #include <uinfo.h>

     int usrinfo (cmd, buf, count)
     int cmd;
     char *buf;
     int count;

Description

     The usrinfo  system call gets and  sets information about
     the owner of  the current process.  The  information is a
     sequence of null-terminated name=value strings.  The last
     string in  the sequence  is terminated by  two successive
     null  characters.   A  child process  inherits  the  user
     information of its parent.

     The buf  parameter is a  pointer to a user  buffer.  This
     buffer is usually UINFOSIZ bytes long.

     The count parameter is the number of bytes of user infor-
     mation to be copied from or to the user buffer.

     If the cmd parameter is one of the following constants:

     GETUINFO    Copies up to count  bytes of user information
                 into the buffer pointed  to by the buf param-
                 eter.

     SETUINFO    Sets the user information  for the process to
                 the first  count bytes in the  buffer pointed
                 to by the buf  parameter.  The effective user
                 ID of  the calling process must  be superuser
                 to set the user information.

     The user  information should at minimum  consist of three
     strings  that are  typically  set by  the login  program.
     These three strings are:

         NAME=username
         UID=userid
         TTY=ttyname

     If the process has no terminal, ttyname should be null.

Return Value

     Upon successful completion,  a nonnegative integer giving
     the  number of  bytes  transferred is  returned.  If  the
     usrinfo system call fails, a  value of -1 is returned and
     errno is set to indicate the error.

Diagnostics

     The usrinfo system call fails if  one or more of the fol-
     lowing are true:

     EPERM      The cmd  parameter is set to  SETUINFO and the
                effective user ID of the process is not super-
                user.

     EINVAL     The cmd  parameter is  not set to  SETUINFO or
                GETUINFO.

     EINVAL     The cmd  parameter is set to  SETUINFO and the
                count parameter is larger than UINFOSIZ.

     EINVAL     The cmd parameter is SETUINFO and buf does not
                contain a NAME= entry.

     EFAULT     The buf parameter &pointsout..

Related Information

     In this book:  "getuinfo."

     The login command in AIX Operating System Commands Refer-
     ence.