I don't use screen, so I'm not at all familiar with it. However, as you suspect, that command substitution will not properly handle the single quotes nor the glob characters (e.g. *, ?, [...], etc) in that screen command-string argument.
As long as it's trusted input, you can try: res=$(eval "$cmd")
Hi all...
This is probably the simplest question but its driving me round the bend :-(
does anyone know how to store a single quote in a variable. Im using cygwin bash
for example
single_qoute = " ' "
echo single_quote
dosnt work :-( it is absolutely baffling me!
The reason why... (4 Replies)
I'm having trouble manipulating a string that contains single quotes (') in it. I'm writing a ksh script to parse in a few queries from a config file, such as this:
findbug \(\(Project 'in' "Deployment,HDRCI,LHS,LSS,WUCI" '&&' Status 'in' "N" '&&' New_on 'lessthan' "070107" \)\) '&&' \(Class... (9 Replies)
I'm not very familiar with the ssh command. When I tried to set a variable and then echo its value on a remote machine via ssh, I found a problem. For example,
$ ITSME=itsme
$ ssh xxx.xxxx.xxx.xxx "ITSME=itsyou; echo $ITSME"
itsme
$ ssh xxx.xxxx.xxx.xxx 'ITSME=itsyou; echo $ITSME'
itsyou
$... (3 Replies)
Hi,
I am trying to create a script which validates the incoming source files. The script has File name Pattern as Argument. The First part of the script validates if there are any files available
if
then
echo "\n Files are available to process \n"
else
echo "\n File does not... (9 Replies)
Hi guys, I have a sed line in double quotes which works fine, but I want it to be in single quotes
here is the sed line
sed "/abc_def/s/\'.*\'/\'\${abc_def}\'/"
can some one give the equivalent to the above script in single quotes
Thanks a ton (5 Replies)
Unix superusers,
I am new to unix but would like to learn more about grep. I am very familiar with regular expressions as i have used them for searching text files in windows based text editors. Since I am not very familiar with Unix, I dont understand when one should use GREP with the... (2 Replies)
Hi I want to replace single quote with two single quotes in a perl string.
If the string is <It's Simpson's book> It should become <It''s Simpson''s book> (3 Replies)
Hi,
Trying to change the prompt. I have the following code.
export PS1='
<${USER}@`hostname -s`>$ '
The hostname is not displayed
<abc@`hostname -s`>$ uname -a
AIX xyz 1 6 00F736154C00
<adcwl4h@`hostname -s`>$
If I use double quotes, then the hostname is printed properly but... (3 Replies)
Discussion started by: bobbygsk
3 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)