re: Shellscripting: Conditional Execution VIEW POST


I really like exit codes
var = $(echo "$((2+2))") & export haspid=$!
echo "$var" | grep 4
if [ $? -eq 0 ] ; then
echo "has num 4 and pid was $haspid"
echo "bash can't add"

Bourne Again SH
Almquist SH
or just Shell
are pretty much the standard as I see it.

I have had to use ksh and csh, just diff formatting...

Plus another vote to bring back t9word and Remove autocorrect


You should use exit statuses directly, not via $?. Like

if command ; then stuff ; fi

Shorter, and save from accidentally picking up the wrong exit code.

Also var = $(echo "$((2+2))") spawns two sub shells, where you only need one: var=$((2+2))


I make it a practice to always use echo and double quotes so that everything inside is resolved like the variables and maybe it is overkill but it is due to habit and also errors that I have seen that come up not using that way in various enviornments

And again putting the
if command;

May lead to again problems with variables and escaping of escapable characters.

Escaping and variables plus nested commands is why I do both practices,.

It's not just overkill, it's useless, and it might have some nasty side effects, too. Here's some more explanation:

If you're having trouble with your variables and escaping characters, you could always fun it in a sub shell and use that error code in the if construct. You're making it overly complicated, and prone to errors.

Idk why everyone has to argue shit on the internet, your own citations says that using echo has its places, and I use what works for me... Not making it complicated just making something that I know works... Just because there is something that also works doesn't make how mine worked wrong...

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