On 04/16/2015 09:09 PM, E.B. wrote:
Don't use bash, of course! Hmm well I didn't not know about this. On CentOS--
lrwxrwxrwx. 1 root root 4 Apr 5 10:31 /bin/sh -> bash*
Can you state the reasons you say do not use bash so I can google about them?
Some random links..
https://wiki.ubuntu.com/DashAsBinSh https://lwn.net/Articles/343924/ http://www.cyberciti.biz/faq/debian-ubuntu-linux-binbash-vs-bindash-vs-binsh...
My summary:
I use Debian. dash is actually a Debian-specific creation. The problem with bash is that it's feature-rich and therefore slow to start and slow to execute. For non-interactive scripts, things like tab-completion or command history are not needed of course. Less-than-bash shells however also do not support more advanced bash syntax.
http://mywiki.wooledge.org/Bashism
/usr/bin/mysql is of course 3 times bigger than /bin/bash and for that matter is also guilty of being unnecessarily friendly to interactive users (via libreadline) ;-)
So I did a very crude test and putting a 'echo select 1 | mysql' in a #!/bin/bash script is only ~20% slower than using #!/bin/sh (which is dash in my case). Oh and it looks like mysql -e blah is a bit faster under bash, but not under dash.
I guess the differences are more meaningful when we're talking about more than (hardly even) one line of shell code.