What is the correct format for a single command that would combine portions of 2 different lines in the command history? I'm using a C shell. Here's a simplified command history to clarify:
4 rm file1
5 ls -ld file2 file3 file4
6 cat file 5
With the above history, what would be the... (5 Replies)
Dear Experts
I am trying to find if it is possible to combine unix commands in awk program. For example if it is possible embed rm or ls or any unix command inside the awk program and while it is reading the file besides printing be able to do some unix commands. I am thinking may be just print... (2 Replies)
I would like to change the lines:
originalline1
originalline2
to:
originalline1new
originalline1newline
originalline2new
originalline2newline
To do this, id like to combine the commands:
sed 's/^/&new/g' file > newfile1
and
sed '/^/ a\\
newline\\
\\ (2 Replies)
Hello all,
I am trying to list and count all the files of a particular type in any given directory. I can use the commands separately but when I combine them they do not give an output.
The command for counting the files is ls -1 | wc -l and for listing all the file of particular type say... (2 Replies)
Is there anyway to achieve "find /home -name "*.bashrc" 2>/dev/null" and "PS1="\n>"" in the same command? I just wanna add a line to the previous command to change the PS1 variable to ">". (1 Reply)
Hi Guys,
I am looking to optimze these 5 SSH lines to a single SSH to get my machine to not hang! lol!
cat hosts.lst | xargs -n1 -t -i echo 'home/util/timeout 6 0 ssh -q {} top -b > util/{}.top &' >> r_query_info
cat hosts.lst | xargs -n1 -t -i echo 'home/util/timeout 6 0 ssh -q {} uname -r... (5 Replies)
hey can anyone tell me how can i combine these two commands so that it is executed only once, but gives me both the results.
IDLE=`sar 30 6 | grep Average | awk '{print $1 $5}' `
sar 30 120 | awk '{print $1" "$5}' >> mailx -m -s "$MSG" xyz@abc.com. (5 Replies)
Hi,
I have a directory with some XML files in it. I can use wildcards to get the list of XMLs I want
say I have following XMLs in same dir
Employee1.xml
Employee2.xml
Employee3.xml
and
Salary1.xml
Salary2.xml
Salary3.xml
apart from other .txt .dat files etc
I want to write a unix... (7 Replies)
Hello all,
I need to send an attachment and text in the body, both in the same Email.
Below are two cammand that send the required data in separate Emails. I need to combine them so that I get just 1 Email containing the attachment & text in the body.
uuencode ${filename} "${file_}" |... (6 Replies)
Discussion started by: Junaid Subhani
6 Replies
LEARN ABOUT CENTOS
shell-quote
SHELL-QUOTE(1) User Contributed Perl Documentation SHELL-QUOTE(1)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 v5.16.3 2010-06-11 SHELL-QUOTE(1)