I don't think this is specific to catalina. In my example, catalina was just an example of a program I was searching for. the output is actually coming from ps -aux. So, it looks like it would always be column 2 unless ps was configured to reorder the columns.
Oh, I thought you were somehow extracting port numbers from ps. PID's make more sense.
But if all you want is PID's, pgrep does everything in one shot without the grep -v grep problem. It's also more portable than ps aux AFAIK.
Quote:
Also, is there a way to do this with xargs?
xargs isn't applicable here; it's not a shell, it doesn't run pipe chains. Running netstat 12 times to find 12 different PID's would be silly, anyway.
Cramming everything into one line doesn't necessarily make it simpler or more efficient.
Hi there,
I am trying to move around 3000 files from one directory to another. The mv command is complaining from too many arguments. I tried to use the xargs command but with no luck. Could some body provide help?
Regards (4 Replies)
I discovered that GNU's xargs has a -P option to allow its processes to run in parallel. Great! Is this a GNU thing, or is it supported by other platforms as well? (4 Replies)
Hi,
I have a requirement to RCP the files from remote server to local server.
Also the RCP has to run in parallel. However using 'xargs' retrives 2 file names during each loop. How do we restrict to only one file name using xargs and loop till remaining files.
I use the below code for... (2 Replies)
Hello there,
Let me show you a simple example of what I am trying to achieve:
1) I have an input text file with some lines:
1 a
2 b
3 c
2) And I want to run a command with these lines as arguments (+ arbitrary extra arguments). For example:
$ command "1 a" "2 b" "3 c" "bye"
I... (7 Replies)
hi
Could any one please tell me the option using which we can run multiple commands using xargs
I have list of files, I want to run dos2unix and chmod at one shot on them
I tried google n searched man pages but couldnt really find the solution , please help
right now im doing this
ls... (4 Replies)
Dear all ,
any suggest on xargs to combine from (1.txt and 2.txt) to output.txt ?
thanks a lot.
1.txt
0123 BUM-5M BUM-5M 93490481 63839
0124 BUM-5M BUM-5M 112112 ... (3 Replies)
Hello, I need some help with xargs
$ ls
aaa bbb ccc ddd$ ls | xargs -I{} ls -la {}
-rw-rw-r--. 1 xxx xx 0 May 30 20:04 aaa
-rw-rw-r--. 1 xxx xx 0 May 30 20:04 bbb
-rw-rw-r--. 1 xxx xx 0 May 30 20:04 ccc
-rw-rw-r--. 1 xxx xx 0 May 30 20:04 dddit's possible to have output like this with... (3 Replies)
Hi,
can anyone tell me in detail ?
what the following do in detail ?
I am trying to get a largest number in a list
Thanks
Tao
LARGEST=$(echo $* | xargs -n1 | sort -nr | tail -1) (3 Replies)
Discussion started by: ccp
3 Replies
LEARN ABOUT CENTOS
shell-quote
SHELL-QUOTE(1) User Contributed Perl Documentation SHELL-QUOTE(1)NAME
shell-quote - quote arguments for safe use, unmodified in a shell command
SYNOPSIS
shell-quote [switch]... arg...
DESCRIPTION
shell-quote lets you pass arbitrary strings through the shell so that they won't be changed by the shell. This lets you process commands
or files with embedded white space or shell globbing characters safely. Here are a few examples.
EXAMPLES
ssh preserving args
When running a remote command with ssh, ssh doesn't preserve the separate arguments it receives. It just joins them with spaces and
passes them to "$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)