Path: utzoo!attcan!utgpu!jarvis.csri.toronto.edu!rutgers!tut.cis.ohio-state.edu!ucbvax!ulysses!hector!ekrell
From: ekrell@hector.UUCP (Eduardo Krell)
Newsgroups: comp.unix.wizards
Subject: Re: shell file descriptor programming (was: Unlinked temp files)
Message-ID: <11566@ulysses.homer.nj.att.com>
Date: 20 May 89 17:14:38 GMT
References: <871@marvin.Solbourne.COM> <1015@philmds.UUCP> <296@tree.UUCP> <4542@psuvax1.cs.psu.edu> <134@minya.UUCP> <11529@ulysses.homer.nj.att.com> <8473@chinet.chi.il.us> <11540@ulysses.homer.nj.att.com> <8494@chinet.chi.il.us>
Sender: netnews@ulysses.homer.nj.att.com
Reply-To: ekrell@hector.UUCP (Eduardo Krell)
Organization: AT&T Bell Laboratories
Lines: 21

In article <8494@chinet.chi.il.us> les@chinet.chi.il.us (Leslie Mikesell) writes:

>That is, add a notation to the
>shell to set the close-on-exec flag when you want it.

Yes, this would be a good compromise, but the POSIX draft doesn't
have such notation.

>BTW, how does ksh know how far to go with
>its file-closing?  I don't recall seeing a handy way to find the
>highest allowable fd other than trying them all until you get an
>error.

The ksh configuration scripts determine how many file descriptors
your system supports (by running a test program which does dup()'s until
it fails) and creates a configuration header file which is used to
compile ksh.
    
Eduardo Krell                   AT&T Bell Laboratories, Murray Hill, NJ

UUCP: {att,decvax,ucbvax}!ulysses!ekrell  Internet: ekrell@ulysses.att.com