Solaris

Hi folks,

I am developer on solaris 8, I am using "here documents <<eof" but unfortunately I am having contention problems with /tmp directory because this facility tries to create a temporary file sh99999 on it but this filename already has been created by a different process before.

To avoid this I had thought on using $TMPDIR variable, but it seems that it only has effect with compilers.

I wonder how I can redirect /tmp directory to another directory only during the execution of my shell script in order to avoid this problem.

Thanks in advance
jterra

I think that the filename is supposed to contain the pid of the shell and this should prevent name collisions. Could these be old filenames from shells that aborted? If so the fix is to address the condition(s) causing the aborts. Another though is to periodically clean out the old files. If neither is possible, crucial scripts can be written to not use here-docs.

Hello Perderabo,
First of all, thanks for your interest.
Yes, you are right, the filename consists of “sh” + pid, and the old filenames correspond to aborted process from operating system because they have as owner “root”. My system administrator has told me that these old files only will be removed at reboot time, but the machine only is rebooted fortnightly. And me as developer I only can try to avoid to allocate sh files on /tmp directory. I also have thought of using real files, but I have a lot of code using here-documents with variables, and before taking that way I would like to know if it were possible to redirect /tmp directory doing the same than compilers.
jterra

Code:

#!/bin/ksh

............

typeset -i u="${$}"

# keep incrementing "u" till you find a non-existant tmp file
while :
do
   tmpFile="/tmp/sh${u}"
   if [ ! -f "${tmpFile}" ] ; then break; fi
   ((u = u + 1 ))
done

command <<EOF >> "${tmpFile}"
.........
.........
EOF

Hello vgersh99,
This is very interesting, but using here-documents I think that sh+pid file is allocated on /tmp automatically, so when system finds <<EOF the automatic allocation is done although later you redirect the output using >> "${tmpFile}". So the problem remains.
jterra

I don't understand.
You have a 'here-doc' that you redirect the output to a temp file. Right?
And that temp might exist with missing 'w' permissions for you to write to. Right?

If that's the case what I'm suggesting is to find a temp file that does not exist. Take a value of '$$' - see if the tempFile exists. If it doesn't - use that file for redirection.
If it does, keep incrementing '$$' till you find the file that does not exist.

Am I missing something obvious here?
It might help if you posted relative parts of your script.

vgersh99's code is not helpful. The shell itself decides on which name to use for here-docs. I suppose that you could keep forking shells until you finally get one with a pid that is not compromised with /tmp/sh* aritifacts, but that really is not a great solution. The answer to the original question is no, /tmp/sh* is hard coded. Your sysadmin's attitude is unfortunate. Had he been willing, this problem could be solved with a clever script to reap the old tmp files. This leaves the option of rewriting the scripts to avoid here-docs.