Spinner Function for Shell Scripts

[Devin Teske]

One-line fix for a small bug (see below).

On Thu, 2010-11-11 at 12:12 -0800, Devin Teske wrote:
> Hi fellow hackers... I come with baring gifts!
> 
> So, just as the subject-line says, ... here's an efficient and robust
> spinner function compatible with many shells.
> 
> But, before I get into the code,
> 
> [snip]
> 
> eval_spin()
> {
> 	local commands=
> 	if [ $# -gt 0 ]; then
> 		# Take commands from positional arguments
> 		while [ $# -gt 0 ]; do
> 			commands="$commands${commands:+ }'$1'"
> 			shift 1
> 		done
> 	else
> 		# Take commands from standard input
> 		while read -r LINE; do
> 			commands="$commands
> $LINE"
> 		done
> 	fi
> 	[ "$commands" ] || return $SUCCESS
> 
> 	#
> 	# Execute the command w/ spinner
> 	#
> 	(
> 		eval "$commands" > /dev/null 2>&1

The above line should instead be:

		  ( eval "$commands" ) > /dev/null 2>&1

To protect from things such as: eval_spin exit



> 		echo $?
> 	) | (
> 		n=1
> 		spin="/-\\|"
> 		DONE=
> 
> 		echo -n " "
> 		while [ ! "$DONE" ]; do
> 			DONE=$( /bin/sh -c 'read -t 0 DONE; echo $DONE' )
> 			printf "\b%s" $( echo "$spin" | sed -e \
> 				"s/.\{0,$(( $n % ${#spin} ))\}\(.\).*/\1/" )
> 			n=$(( $n + 1 ))
> 		done
> 		printf "\b \b"
> 		exit $DONE
> 	)
> }
> 
> [snip]
-- 
Cheers,
Devin Teske

-> CONTACT INFORMATION <-
Business Solutions Consultant II
FIS - fisglobal.com
510-735-5650 Mobile
510-621-2038 Office
510-621-2020 Office Fax
909-477-4578 Home/Fax
devin.teske at fisglobal.com

-> LEGAL DISCLAIMER <-
This message  contains confidential  and proprietary  information
of the sender,  and is intended only for the person(s) to whom it
is addressed. Any use, distribution, copying or disclosure by any
other person  is strictly prohibited.  If you have  received this
message in error,  please notify  the e-mail sender  immediately,
and delete the original message without making a copy.

-> END TRANSMISSION <-