From: Bertram Scharpf <lists@...>
Date: 2005-01-19T06:12:05+09:00
Subject: Bug: backquotes report error

Hi,

there is something wrong with backquotes:

    $ uname
    Linux
    $ ruby -e 'puts RUBY_VERSION'
    1.8.2
    $ ruby -e '`ls`'
    $ ruby -e '`exit 23`'
    -e:1: command not found: exit 23
    $ ruby -e '`echo -n ; exit 23`'
    $ ruby -e '`exit 23 ; cat`'
    $ ruby -e '`exit 23 ; `'
    $ ruby -e '`read`'
    -e:1: command not found: read
    $ ruby -e '`echo -n ; read`'
    $

I hacked the interpreter and located the problem at
`process.c', functions `rb_proc_exec()' and `proc_exec_v()'.
(The loop in the former function doesn't actually reveal its
purpose to me.)

I find in either case the `exit 23' being executed once as

    exec..( '/bin/sh', '-c', 'exit 23')

and another time as

    exec..( 'exit', '23')

which is not recognized as a shell builtin.

I admit this is puzzling because of the dozens of different
operating systems to consider.

Bertram Scharpf

--
Bertram Scharpf
Stuttgart, Deutschland/Germany
http://www.bertram-scharpf.de