Hi, first post, so hello to all.
I have a Bash scripting problem that is driving me a bit nutty.
It involves a program called 'convert' which is part of the ImageMagick collection.
Normal usage from the commandline is:
$ convert -resize 120x120 inputfile.jpg outputfile.jpg
This is... (7 Replies)
hi,
please point out what's wrong with my script. im feeding it a list containing fqdn, sit should ssh into each and verify that atleast one of its virtual backup ip resolves into one of its virtual hostnames .. anyway the objective shows in the script... however, im having problems in the ... (4 Replies)
Hi, I am a nbee to Unix, I have used following script to check my tomcat is running or not and restart if it down. but actually it restart my tomcat each time running even my tomcat still running fine:
Script that can run a check and perform an action if the check fails
... (1 Reply)
I want to combine 2 conditional statements by using -o in bash, but it won't work.
if ; then
echo "The number needs to be between 0 and $nr"
fi
Each time i execute the file it says:
./selectCitaat: line 10: syntax error near unexpected token `$1' (3 Replies)
Hi,
Does anyone know any way of making bash prompt extended with conditional content?
Example:
export PS1="] && echo '#' || echo '\$'" # This won't work - prompt is not executed
# export PS1="\$" # This is an existing but also working equivalent
I would like to use more complex... (8 Replies)
I want to let sleep 3 in the background and echo $i
pkglists="a b c d e f g"
f()
{
local i
set -- $pkglists
&& ((i +=2)) && sleep 3 &;echo $i
}
f (3 Replies)
I think(hope) I've got a simple one - I just need to send an email if a mysql query returns any results (ideally - it will never match).
Currently I just pipe the mysql query output to the mail program, but of course that emails regardless of the output( and I check this every 10 minutes from... (5 Replies)
Discussion started by: jcass78
5 Replies
LEARN ABOUT DEBIAN
shell-quote
SHELL-QUOTE(1p) User Contributed Perl Documentation SHELL-QUOTE(1p)NAME
shell-quote - quote arguments for safe use, unmodified in a shell command
SYNOPSIS
shell-quote [switch]... arg...
DESCRIPTION
shell-quote lets you pass arbitrary strings through the shell so that they won't be changed by the shell. This lets you process commands
or files with embedded white space or shell globbing characters safely. Here are a few examples.
EXAMPLES
ssh preserving args
When running a remote command with ssh, ssh doesn't preserve the separate arguments it receives. It just joins them with spaces and
passes them to "$SHELL -c". This doesn't work as intended:
ssh host touch 'hi there' # fails
It creates 2 files, hi and there. Instead, do this:
cmd=`shell-quote touch 'hi there'`
ssh host "$cmd"
This gives you just 1 file, hi there.
process find output
It's not ordinarily possible to process an arbitrary list of files output by find with a shell script. Anything you put in $IFS to
split up the output could legitimately be in a file's name. Here's how you can do it using shell-quote:
eval set -- `find -type f -print0 | xargs -0 shell-quote --`
debug shell scripts
shell-quote is better than echo for debugging shell scripts.
debug() {
[ -z "$debug" ] || shell-quote "debug:" "$@"
}
With echo you can't tell the difference between "debug 'foo bar'" and "debug foo bar", but with shell-quote you can.
save a command for later
shell-quote can be used to build up a shell command to run later. Say you want the user to be able to give you switches for a command
you're going to run. If you don't want the switches to be re-evaluated by the shell (which is usually a good idea, else there are
things the user can't pass through), you can do something like this:
user_switches=
while [ $# != 0 ]
do
case x$1 in
x--pass-through)
[ $# -gt 1 ] || die "need an argument for $1"
user_switches="$user_switches "`shell-quote -- "$2"`
shift;;
# process other switches
esac
shift
done
# later
eval "shell-quote some-command $user_switches my args"
OPTIONS --debug
Turn debugging on.
--help
Show the usage message and die.
--version
Show the version number and exit.
AVAILABILITY
The code is licensed under the GNU GPL. Check http://www.argon.org/~roderick/ or CPAN for updated versions.
AUTHOR
Roderick Schertler <roderick@argon.org>
perl v5.8.4 2005-05-03 SHELL-QUOTE(1p)