02-04-2013
What do you mean with
? Do you want to make the file size equals zero, i.e. an empty file?
10 More Discussions You Might Find Interesting
1. UNIX for Dummies Questions & Answers
Maybe it's an stupid question but remeber... I'm Junior..
I use command line to run programs, and some of them gives a lot of information when, for example, you open a window or other actions. That's really bad because my terminal gets full of unwanted messages, so I use "bin file & >/dev/null"... (1 Reply)
Discussion started by: piltrafa
1 Replies
2. UNIX for Dummies Questions & Answers
im having trouble with moving files in a directory into /dev/null
for file in $HOME/.trashcan/
do
mv $file /dev/null
done
the error msg i get is:
mv: /dev/null: not a directory.
does anyone know how to fix this?
thanks
primal (16 Replies)
Discussion started by: primal
16 Replies
3. UNIX for Dummies Questions & Answers
Hi ,
I am importing some table from /dev/null i dont understand what is /dev/null
Sorry i am new to UNIX
sam71 (3 Replies)
Discussion started by: sam71
3 Replies
4. UNIX for Advanced & Expert Users
Hi,
Q1-What does
nroff -ms > /dev/null
Q2- What does mean -A under STAT column :
ps aux |head -20
UTIL PID %CPU %MEM SZ RSS TTY STAT STIME TIME COMMAND
root 516 93,0 0,0 12 12 - A 04 nov 3906:51 wait
Thank you. (4 Replies)
Discussion started by: big123456
4 Replies
5. Shell Programming and Scripting
hello all,
In many shell scripts i found '> /dev/null' , i am not able to get this,
will any one please explain why we are using this.
thanks
sudha (2 Replies)
Discussion started by: rrs
2 Replies
6. Solaris
Hi, Anyone can help
My solaris 8 system has the following
/dev/null , /dev/tty and /dev/console
All permission are lrwxrwxrwx
Can this be change to a non-world write ??
any impact ?? (12 Replies)
Discussion started by: civic2005
12 Replies
7. UNIX for Dummies Questions & Answers
How are these two different? They both prevent output and error from being displayed. I don't see the use of the "&"
echo "hello" > /dev/null 2>&1
echo "hello" > /dev/null 2>1 (3 Replies)
Discussion started by: glev2005
3 Replies
8. Shell Programming and Scripting
I apologize if this question has been answered else where or is too elementary.
I ran across a KSH script (long unimportant story) that does this:
if ; then
CAS_SRC_LOG="/var/log/cas_src.log 2>&1"
else
CAS_SRC_LOG="/dev/null 2>&1"
fithen does this:
/usr/bin/echo "heartbeat:... (5 Replies)
Discussion started by: jbmorrisonjr
5 Replies
9. Shell Programming and Scripting
Hello All and a Happy New year to yous guys.
I'm running the below command on my AIX box and it keeps giving me the message that the file doesn't exist. I know the file don't exist, but I don't want to see the error. 2>/dev/null doesn't work.
bash-3.00$ ls -l C* | wc -l 2>/dev/null
ls:... (2 Replies)
Discussion started by: bbbngowc
2 Replies
10. Shell Programming and Scripting
Friends have the following problem
a search may not find anything which would correct example:
ls -ltr *prueba.txt | nawk '{ print $9 }' > Procesar.dat 2>/dev/null
When he finds nothing gives me the following error
ls: prueba.txt: No such file or directory
because 2> / dev / null... (4 Replies)
Discussion started by: tricampeon81
4 Replies
LEARN ABOUT DEBIAN
shell-quote
SHELL-QUOTE(1p) User Contributed Perl Documentation SHELL-QUOTE(1p)
NAME
shell-quote - quote arguments for safe use, unmodified in a shell command
SYNOPSIS
shell-quote [switch]... arg...
DESCRIPTION
shell-quote lets you pass arbitrary strings through the shell so that they won't be changed by the shell. This lets you process commands
or files with embedded white space or shell globbing characters safely. Here are a few examples.
EXAMPLES
ssh preserving args
When running a remote command with ssh, ssh doesn't preserve the separate arguments it receives. It just joins them with spaces and
passes them to "$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)