Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: utzoo!henry From: henry@utzoo.UUCP (Henry Spencer) Newsgroups: net.unix Subject: Re: why doesn't this shell program work Message-ID: <5150@utzoo.UUCP> Date: Sun, 3-Mar-85 00:26:30 EST Article-I.D.: utzoo.5150 Posted: Sun Mar 3 00:26:30 1985 Date-Received: Sun, 3-Mar-85 00:26:30 EST References: <2147@drutx.UUCP> Organization: U of Toronto Zoology Lines: 8 The pipe is causing the main shell to spin off a child shell to run the innards of the for-loop. The result is that the variable is local to the child, and naturally doesn't propagate back into the parent since there is no path by which it might do so. You have just encountered Excedrin Headache number 3.14159 for shell programmers. -- Henry Spencer @ U of Toronto Zoology {allegra,ihnp4,linus,decvax}!utzoo!henry