Is /bin/sh must link to /usr/bin/bash?

dlin · 2013-01-31 05:18:36

I'm building Arch Linux on embedded system which CPU is sh4.
I found there is a problem of bash package.
It creates /bin/sh as a symbolic link to /usr/bin/bash.

But my /bin/sh is busybox.
1. I'm wonder how could I keep /bin/sh to busybox's /bin/sh? Or, it could set on pacman.conf?
2. Could my root account still use 'sh' as its shell? I wish busybox could still exist as the basement.
3. Is makepkg or yaourt based on root's shell must be bash?

Scimmia · 2013-01-31 05:49:44

IIRC, pacman requires bash. It doesn't have to be the login shell, but it has to exist. The login shell can be whatever you want.

Edit, let me clarify that a bit. Anything that needs bash calls bash specifically, so it doesn't matter what the root login shell is.

Last edited by Scimmia (2013-01-31 05:53:57)

Allan · 2013-01-31 06:02:11

Many of the Arch package post_install scriptlets are written assuming bash, and pacman uses /bin/sh as its shell. In 4.1, this will be configurable. Makepkg uses /bin/bash.

dlin · 2013-01-31 06:30:15

Thank you Allan,

I have this question is because /usr/bin/bash require many dynamic library and I just failed login my embedded system after upgrade bash with pacman -Udd option.

Am I right of the following assumption (Sorry, I can not 100% understand your meaning, require double confirm.).

1. I can keep my root's shell as /bin/sh (it's busybox version).
2. I can config pacman to use /bin/bash for install (I've compiled brand new pacman)
3. makepkg have forced to use /bin/bash for install

BTW, I found it is required bash 4.0 (declare function) My embedded system's original linux only provide bash 3.0. So, it took me a while to prepare bash 4.0.

Last edited by dlin (2013-01-31 06:42:22)

Allan · 2013-01-31 06:36:16

1 and 3 are right. 2 is only possible with the developmental version of pacman.

progandy · 2013-01-31 06:36:21

2. I can config pacman to use /bin/bash for install (I've compiled brand new pacman)

Since you are compiling pacman, you can simply replace /bin/sh with /usr/bin/bash in the source. And add /bin/sh to NoExtract in pacman.conf

dlin · 2013-02-01 21:59:39

Instead of assign /bin/bash, is it possible check do following to provide minimal dependency?

if /bin/bash exist and workable (link successful) then
call /bin/bash.
else
call /bin/sh
fi

dlin · 2013-02-04 05:30:38

where to found out the code of development pacman?
I've try search /bin/sh on the current downloaded pacman 4.0.3-5 source.
And the founding can not help to modify the source to force it to use /bin/bash.
The only line mentioned about /bin/sh is in download_with_xfercommand() of src/pacman/conf.c

But, I don't think it is correct place to modify it.

pm_printf(ALPM_LOG_DEBUG, "running command: %s\n", parsedcmd);
        retval = system(parsedcmd);

I try to modify as

char buf[1024];
sprintf(buf, "/bin/bash -c %s", parsedcmd)
pm_printf(ALPM_LOG_DEBUG, "running command: %s\n", buf);
        retval = system(buf);

Last edited by dlin (2013-02-04 05:58:05)

Arch Linux

#1 2013-01-31 05:18:36

Is /bin/sh must link to /usr/bin/bash?

#2 2013-01-31 05:49:44

Re: Is /bin/sh must link to /usr/bin/bash?

#3 2013-01-31 06:02:11

Re: Is /bin/sh must link to /usr/bin/bash?

#4 2013-01-31 06:30:15

Re: Is /bin/sh must link to /usr/bin/bash?

#5 2013-01-31 06:36:16

Re: Is /bin/sh must link to /usr/bin/bash?

#6 2013-01-31 06:36:21

Re: Is /bin/sh must link to /usr/bin/bash?

#7 2013-02-01 21:59:39

Re: Is /bin/sh must link to /usr/bin/bash?

#8 2013-02-04 05:30:38

Re: Is /bin/sh must link to /usr/bin/bash?

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