If local system management policies require that private tmp and imdir directories be defined for each user, you can define these directories for each user as subdirectories of their SYS$LOGIN directory. One way to do this is define imdir to be the same as tmp, and modify the definition of IRAFTMP in the IRAFUSER.COM file as shown below.

$! ----------- add these lines to irafhlib:irafuser.com ---------- 
$! This block of DCL assigns the logical name IRAFTMP to a 
$! subdirectory of the user's VMS login directory.  It is necessary 
$! to escape the "$" and "[" because they are IRAF filename 
$! metacharacters.  This block of code should replace the current 
$! definition in irafuser.com of IRAFTMP: 
$! 
$!   define/job  IRAFTMP  TEMPDISK:[IRAFTMP]        ! scratch files 
$! 
$! We assume only one occurrence of "$" or "[". 
$! 
$  tmpdir = f$logical ("SYS$LOGIN") 
$  tmpdir = f$extract (0, f$locate("]",tmpdir), tmpdir) + ".IRAFTMP]" 
$  define/job vmstmp 'tmpdir' 
$  off = f$locate ("$", tmpdir) 
$  tend = f$length (tmpdir) 
$  if (off .ne. tend) then -    
     tmpdir = f$extract (0, off, tmpdir) + -
     "\$" + f$extract (off+1, tend, tmpdir) 
$  off = f$locate ("[", tmpdir) 
$  if (off .ne. tend+1) then -
     tmpdir = f$extract (0, off, tmpdir) + -
     "\[" + f$extract (off+1, tend, tmpdir) 
$  define/job iraftmp "''tmpdir'" 

In irafhlib:mkiraf.com, replace the block of statements beginning "imdir_file :=" with the following:

$  if (f$search ("sys$login:iraftmp.dir") .eqs. "") then -
   create/directory vmstmp