Configuration Information [Automatically generated, do not change]:
Machine: i386
OS: linux-gnu
Compiler: gcc
Compilation CFLAGS: -DPROGRAM='bash' -DCONF_HOSTTYPE='i386'
-DCONF_OSTYPE='linux-gnu' -DCONF_MACHTYPE='i386-pc-linux-gnu'
-DCONF_VENDOR='pc' -DLOCALEDIR='/usr/share/locale' -DPACKAGE='bash' -DSHELL
-DHAVE_CONFIG_H -I. -I../bash -I../bash/include -I../bash/lib -g -O2
uname output: Linux amidala 2.6.9 #4 Sun Nov 14 11:41:20 WST 2004 i686 GNU/Linux
Machine Type: i386-pc-linux-gnu
Bash Version: 3.0
Patch Level: 0
Release Status: release
Description:
(Same bug filed at savannah (#103583), but an SMTP error from the web page
when I submitted it tells me that nobody may have received it).
With some elaborate redirections, it appears that some file descriptors are
not being closed prior to spawning off processes. After running the script
below, one can observe the FDs of the sleep process by typing:
$ ls -l /proc/`pidof sleep`/fd/
total 4
lr-x------ 1 b b 64 Nov 18 18:32 0 -> /dev/null
l-wx------ 1 b b 64 Nov 18 18:32 1 -> /dev/null
l-wx------ 1 b b 64 Nov 18 18:32 10 -> pipe:[245971]
l-wx------ 1 b b 64 Nov 18 18:32 2 -> /dev/null
As you can see, there is an extra FD 10 there which is inherited by sleep.
The other end of that pipe is attached to the script. Hence the script will
hang until the sleep process terminates (or whatever other long-lived
process or daemon is spawned by this script).
Looking at bash's source, it appears related to the add_undo_redirect
function in redir.c and its actions. (I suspect the issue is that the FD
is getting its close-on-exec flag cleared inadvertently).