#763511 menu depends on bash

Package:
menu
Source:
menu
Description:
generates programs menu for all menu-aware applications
Submitter:
Date:
2014-10-01 13:24:13 UTC
Severity:
normal
#763511#5
Date:
2014-09-30 15:44:54 UTC
From:
To:

hello,

when i invoke update-menu on a debian jessie system without the bash
shell being installed the following error is shown:

# update-menus -d -v
sh: 1: exec: /bin/bash: not found
Unknown error, message=exec /bin/bash -o pipefail -c 'dpkg-query --show
--showformat="\${status} \${provides} \${package}\n" | sed -n -e
"/installed\|triggers-awaited\|triggers-pending
/{s/^.*\(installed\|triggers-awaited\|triggers-pending\) *//; s/[, ][,
]*/\n/g; p}"'


when setting an alternative to the dash shell it results in this error:

# update-menus -d -v
update-menus[22707]: Dpkg is not locking dpkg status area, good.
update-menus[22707]: Reading installed packages list...
/bin/bash: 0: Illegal option -o pipefail
Unknown error, message=exec /bin/bash -o pipefail -c 'dpkg-query --show
--showformat="\${status} \${provides} \${package}\n" | sed -n -e
"/installed\|triggers-awaited\|triggers-pending
/{s/^.*\(installed\|triggers-awaited\|triggers-pending\) *//; s/[, ][,
]*/\n/g; p}"'


this is caused by an hardcoded dependency on the bash shell that is not
mentioned in the packages dependency list.


best regards,
gabriel




# uname -a
Linux 3.16-2-amd64 #1 SMP Debian 3.16.3-2 (2014-09-20) x86_64 GNU/Linux

# dpkg -s libc6 | grep '^Version'
Version: 2.19-11
#763511#10
Date:
2014-09-30 16:16:08 UTC
From:
To:
Hello Gabriel,

bash is marked 'Essential: yes' so according to Debian policy, packages
ust not add dependencies on bash.
See policy 3.5:

     Packages are not required to declare any dependencies they have on
     other packages which are marked `Essential' (see below), and should
     not do so unless they depend on a particular version of that
     package.[1]

And 10.4:

     If a shell script requires non-SUSv3 features from the shell
     interpreter other than those listed above, the appropriate shell must
     be specified in the first line of the script (e.g., `#!/bin/bash') and
     the package must depend on the package providing the shell (unless the
     shell package is marked "Essential", as in the case of `bash').

In this instance, bash is required because I do not know how to implement
the equivalent of '-o pipefail' with a POSIX shell.

Cheers,
#763511#15
Date:
2014-10-01 10:50:35 UTC
From:
To:

Hi Bill,


thanks for pointing this out. I did not know how to ipmlement pipefail
in a POSIX conformal way either and searching on the internet didn't
give me any results of interest for this situation.

But in general I think it should be possible to circumvent the pipefail
here by storing the results of the dpkg query in some sort of structure
and process it with C++-style string routines.

I'm not sure whether I'll find the time to do the programming for that
but would you be interested at all?


Cheers,
Gabriel
#763511#20
Date:
2014-10-01 13:13:04 UTC
From:
To:
Yes, it is rather a shame POSIX sh does not provide a simple way to get the
return status of the first pipe element.

Sure, if this is not too wordy.

Cheers,
Bill.