/proc/$$/fd mystery - {t,}csh vs. bash

[Michael ODonnell]

OK - this is at least a minor case of WTF - why is it that
the list of active file descriptors shown when {t,}csh is
running shows no descriptor lower than 15 ?!?

 ######## e521:~ 711---> /bin/bash
 ######## e521:~ 513---> echo My PID is $$, contents of my /proc/$$/fd follow... ; ls -l /proc/$$/fd
 My PID is 27237, contents of my /proc/27237/fd follow...
 total 0
 lrwx------ 1 mod mod 64 2009-01-08 20:47 0 -> /dev/pts/0
 lrwx------ 1 mod mod 64 2009-01-08 20:47 1 -> /dev/pts/0
 lrwx------ 1 mod mod 64 2009-01-08 20:47 2 -> /dev/pts/0
 lrwx------ 1 mod mod 64 2009-01-08 20:47 255 -> /dev/pts/0
 ######## e521:~ 514---> /bin/tcsh
 e521:~> echo My PID is $$, contents of my /proc/$$/fd follow... ; ls -l /proc/$$/fd
 My PID is 27240, contents of my /proc/27240/fd follow...
 total 0
 lrwx------ 1 mod mod 64 2009-01-08 20:47 15 -> /dev/pts/0
 lrwx------ 1 mod mod 64 2009-01-08 20:47 16 -> /dev/pts/0
 lrwx------ 1 mod mod 64 2009-01-08 20:47 17 -> /dev/pts/0
 lrwx------ 1 mod mod 64 2009-01-08 20:47 18 -> /dev/pts/0
 lrwx------ 1 mod mod 64 2009-01-08 20:47 19 -> /dev/pts/0
 e521:~> /bin/bash
 ######## e521:~ 513---> echo My PID is $$, contents of my /proc/$$/fd follow... ; ls -l /proc/$$/fd
 My PID is 27242, contents of my /proc/27242/fd follow...
 total 0
 lrwx------ 1 mod mod 64 2009-01-08 20:47 0 -> /dev/pts/0
 lrwx------ 1 mod mod 64 2009-01-08 20:47 1 -> /dev/pts/0
 lrwx------ 1 mod mod 64 2009-01-08 20:47 2 -> /dev/pts/0
 lrwx------ 1 mod mod 64 2009-01-08 20:47 255 -> /dev/pts/0
 ######## e521:~ 514---> /bin/csh
 e521:~> echo My PID is $$, contents of my /proc/$$/fd follow... ; ls -l /proc/$$/fd
 My PID is 27244, contents of my /proc/27244/fd follow...
 total 0
 lrwx------ 1 mod mod 64 2009-01-08 20:47 15 -> /dev/pts/0
 lrwx------ 1 mod mod 64 2009-01-08 20:47 16 -> /dev/pts/0
 lrwx------ 1 mod mod 64 2009-01-08 20:47 17 -> /dev/pts/0
 lrwx------ 1 mod mod 64 2009-01-08 20:47 18 -> /dev/pts/0
 lrwx------ 1 mod mod 64 2009-01-08 20:47 19 -> /dev/pts/0