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-binshshell/
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.
