Shell Programming and Scripting

Hi,

In a bash script, I'm using kill -0 to test if I have permission to kill a process. There are 3 cases:
- the process exists and I have permission: OK
- the process doesn't exist and it's OK (because I decided to ignore processes that are already dead).
- I don't have permission and I want to raise an error.

If I use ps $pid, I cannot tell the difference between a process that does not exist and a process I cannot "see":

Code:

santiago@alphard:~$ ps 1 > /dev/null && echo OK || echo ERR
ERR
santiago@alphard:~$ sudo ps 1 > /dev/null && echo OK || echo ERR
OK

If I use kill -0 $pid, I could tell the difference reading stderr but it would be language specific:

Code:

santiago@alphard:~$ for pid in 1 123; do for lc in C fr_FR.utf-8; do LC_ALL=$lc; kill -0 $pid; echo Status is $?; done; done
-su: kill: (1) - Operation not permitted
Status is 1
-su: kill: (1) - Opération non permise
Status is 1
-su: kill: (123) - No such process
Status is 1
-su: kill: (123) - Aucun processus de ce type
Status is 1

Question: How can I programmatically tell if a process exists and if I have permission on it?

Regards
Santiago