Any Bash features you'd like to see?

[Peter]

On Wed, 11 May 2005, Chris F.A. Johnson wrote:

>   X window commands, e.g.:
>
> window=$(openwindow -geometry 600x300+10+10)
> drawline $window 10 10 30 100
> text $window "Hello, world."
> closewindow $window

;-) There are a few command line programs that do that already (maybe 
not at that level, you can't draw afaik). But why not go all the way and 
bind several shells into a 'gshell' that would act as a wrapper and 
transfer variables between the instances. Maybe it could handle 
setting up pipes so programs can talk to each other while running 
under it. Sample (totally fictitious):

#!/bin/gshell
#
# gshell stands for godzilla shell ;-)
#
WORKDIR=/some/where
# run commands under bash
# escape any curly braces in $*
SSTAR=`echo "$*"|sed -e 's/{/\{/g' -e 's/}/\}/g'`
!/bin/bash $SSTAR {
 	PWD=`pwd`
 	cd ${WORKDIR}
 	. ./config.cfg
 	# start something in the background, via bash
 	nohup mydaemon ${OPTS} $SSTAR &
 	PID=$!
}
# run a process under another instance of bash in the background - 
# similar to what was done above, but different:
! $SSTAR {
 	cd ${WORKDIR}
 	# the '&' below puts the task in the background
 	!/bin/bash $* { &
 		. ./soft-daemon.sh ${OPTS} $SSTAR
 	}
 	PID=$!
 	LOST="something that will be lost"
 	export PID
}
# end context: undoes cd ${WORKDIR} and any shell variables set in the context 
# and not exported are unset
# run commands under wish: gshell unescapes '\{' to '{' below etc
!/usr/bin/wish -- -foo "\{bar baz ${PID}\}" {
 	set pid [lindex [lindex $argv 3] 2]
 	wm title . {myapp: $pid}
 	label .l -text "Myapp (daemon PID=$pid)"
 	# etc etc
 	set logf [open $logfn {WRONLY APPEND CREAT}
 	# etc etc
 	puts $logf "$logstamp session end"
 	close $logf
}
# write a report using perl and mail errors somewhere if necessary
!/usr/bin/perl -W {
 	# perl code here
}
# exit with a code
exit 0

As you can see this is not very hard (famous last words) as each context 
or instance can be implemented as a standalone shell script after very 
simple text manipulation.

just fantasy (for now),
Peter
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