On 3/2/06, Kevin B. McCarty <[EMAIL PROTECTED]> wrote: > Hi list, > > Could someone tell me why the following works in zsh but not in > bash/posh/dash? > > benjo[3]:~% echo foo bar baz | read a b c > benjo[4]:~% echo $a $b $c > foo bar baz > > If I try the same with bash (or other sh-compatible shells), the > variables $a $b and $c are unset. From the bash man page: > ... > So "read" claims to read from the standard input, but it doesn't > actually seem to happen when a pipe is involved.
What's happening here is that the pipe is causing a subshell to be spawned, which is then parsing the command "read a b c". > Posh and dash behave like bash in this respect, so I guess that this is > not a bug, and that what zsh does is actually an extension. So, what is > the correct POSIX-compatible way to get "read" to work as I want? Yeah, I would guess that zsh is doing something really funky to make this work -- passing variables from a subprocess back up to the parent, or not actually spawning a subprocess with the pipe, or something like that. I'm not sure of the POSIX way to use read in this manner, but I found this on Google/A9: http://linuxgazette.net/issue57/tag/1.html The example he gives, with the < <() syntax, worked in bash, but not in Debian or FreeBSD's /bin/sh.
