bug-bash
[Top][All Lists]
Advanced

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: lost output from asynchronous lists


From: Eric Blake
Subject: Re: lost output from asynchronous lists
Date: Wed, 29 Oct 2008 06:26:56 -0600
User-agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.8.1.17) Gecko/20080914 Thunderbird/2.0.0.17 Mnenhy/0.7.5.666

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

According to Eric Blake on 10/29/2008 6:22 AM:
>>> -  ( :; $1 ) >"$at_stdout" 2>"$at_stderr"
>>> +  : >"$at_stderr"
>>> +  ( :; $1 ) >>"$at_stdout" 2>>"$at_stderr"
>> What's the ":;" for?
> 
> A workaround to the bash 3.2 bug, fixed in bash32-030, where failure to
> use :; prior to a compound command (except for a subshell) meant that bash
> incorrectly returns status 0 if redirection fails.

Sorry; I thought it was a different use of :;.  In this case, it is a
workaround to the case where the m4 argument $1 is empty or only
whitespace, and is necessary so that the shell code formed is valid (a
subshell must contain a command list).

- --
Don't work too hard, make some time for fun as well!

Eric Blake             address@hidden
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.9 (Cygwin)
Comment: Public key at home.comcast.net/~ericblake/eblake.gpg
Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org

iEYEARECAAYFAkkIVpAACgkQ84KuGfSFAYAWSQCcCyrB7+SwucDf94O8CIuU1qHP
ApIAn3LadaOwxW+j+hzsDUHnYXV01mSX
=Qptm
-----END PGP SIGNATURE-----




reply via email to

[Prev in Thread] Current Thread [Next in Thread]