Arch Linux

When booting, there is an error message like

/etc/bash_completion.d/git: line 123: syntax error near unexpected token "<".

In my opinion, this problem is due to Arch's shell setting, which links /bin/sh to /bin/bash. So that any process which start a sh shell, it actually starts a bash shell. However, in /etc/profile, there is a bash script used to detect shell:

shell="sh"
if test -f /proc/mounts; then
case $(/bin/ls -l /proc/$$/exe) in
*bash) shell=bash ;;
*dash) shell=dash ;;
*ash) shell=ash ;;
*ksh) shell=ksh ;;
*zsh) shell=zsh ;;
esac
fi

It use /proc/$$/exe to determine the shell name. The problem is, if you start a sh shell, /proc/$$/exe will also show "bash"

$ sh
$ ls -l /proc/$$/exe
lrwxrwxrwx 1 elf hal 0 Sep 24 12:53 /proc/4646/exe -> /bin/bash

So if you start a sh, and run /etc/profile, it will also try to run bash_completion, which will lead to an error:

$ sh /etc/profile
/etc/bash_completion.d/git: line 123: syntax error near unexpected token `<'
/etc/bash_completion.d/git: line 123: ` done < <(git config -z --get-regexp '^(svn-remote\..*\.url|bash\.showupstream)$' 2>/dev/null | tr '\0\n' '\n ')'

In my opinion, the detecting method in /etc/profile is not correct. It should distinguish sh and bash. When the process start a sh (for example, gdm at booting), /etc/profile should not try to run /etc/profile.bash and /etc/bash.bashrc. It should try to find /etc/profile.sh, as written in the script.

By the way, the line

[ -r /etc/bash_completion ] && . /etc/bash_completion

in bash.bashrc is not necessary now, because bash_completion package has already contained a script in /etc/profile.d. So it is proper remove this line in bash package. However, this is another problem.