Re: Gnus ignores exit value of `sendmail-program'

On Thu, 06 Jun 2002 12:16:07 +0200, Simon Josefsson said: This is an artifact of how #! came to be, and how it works. A long time ago, in a Unix version far away, there was only /bin/sh and exec*(). So if you gave a command name, the shell would try to fork()/exec() it, and if it failed, it would fork() and then try to read the file as a shell script. Then when multiple shells came into existence, it got changed to "if it failed, it would fork(), then run either ourselves or $SHELL to read it as input". Then #! got added for flexibility and efficiency, as you could have it run under a shell other than $SHELL and save a trip or two into the kernel (which was REALLY important back on the 750/780 class systems). And in fact, if $SHELL is set to something that signals an error on an unexpected end-of-file, it might *NOT* return zero when invoking an empty file.... Unfortunately, this has just too many subtle side effects - I've seen systems where /bin/true and /bin/false rely on this sort of thing. Yes, that's brain dead - /bin/true and /bin/false should be 'main() {return(0)}' type things (why they are 9144 bytes in size on RedHat 7.3 is code bloat at its finest...) -- Valdis Kletnieks Computer Systems Senior Engineer Virginia Tech