Hallo everyone
I might just be being dumb, but I am using the BASH shell and cannot get the following script to work:
x=0
while
do
echo $x
x=´echo "$x + 1" | bc´
done
Can anybody help me out. I am just get a repeating output saying:
bc: command not found
0 + 1: command not... (5 Replies)
I'm just trying to make a script that runs in command line to echo each line in a text file. Everything i found on google is telling me to do it like this but when I run it it just echos removethese.txt and thats it. Anyone know what im doing wrong?
for i in removethese.txt; do echo $i; done
... (4 Replies)
i have the following process running in background:
when i give "ps -lef"
------------------------------------------------------------------------
user2
user1
user1
user3
user1
user4
user5
user4
user3
user4
user2
user1
user1
user3
user1
user4 (3 Replies)
i have a script called file2
#!/bin/ksh
i=0
while
do
echo $i >> result.txt
i=`expr $i + 1`
done
echo "***********************" >> result
------------------------------------------------------------------- (10 Replies)
I have what I believe is a simple programming question. I have a text file that looks like:
mol 1 G:\stereo01.hin
block text
...
...
...
endmol 1
However, I would like a file that repeats this entire block of text several times over. The lines of text in the middle remain the same for each... (2 Replies)
Hi expert,
I'm using csh
Code:
#!/bin/csh
set x = 0
set number = `awk '{array=$0} END {print array;}'`
i want to use for loop to store data to $number repeatly
untill x = 23
How to use c shell for loop? (2 Replies)
I need to chmod a bunch of files with a specific extension in one directory.
If I understand correctly first I would run ls command like this
ls -R | grep .mp3 > /tmp/list
once I have the output file I should be able to run a loop to chmod all the files in the list created.
This is where... (5 Replies)
Hello forum memebers.
can you correct the simple while program.
#! /bin/ksh
count=10
while
do
echo $count
count='expr$count-1'
done
I think it will print 10 to 1 numbers but it running for indefinite times. (2 Replies)
Does any body can help me with a loop in this example?
if
then
if
then
runner=$(grep "$1" "$2")
runne=$(grep "$1" "$3")
run=$(grep "$1" "$4")
fi
fi
#
# Message on screen... (3 Replies)
Dear experts,
I am writing a bash script. At some point of the program I need to have 'for' loop. For simplicity I tried with some other simple code. The format of the loop is given below.
k=51
m=55
for j in {$k..$m};do
w=$(($j+2))
z=$(($j+9))
echo "$w, $z"
done
But my... (4 Replies)
Discussion started by: vjramana
4 Replies
LEARN ABOUT CENTOS
shell-quote
SHELL-QUOTE(1) User Contributed Perl Documentation SHELL-QUOTE(1)NAME
shell-quote - quote arguments for safe use, unmodified in a shell command
SYNOPSIS
shell-quote [switch]... arg...
DESCRIPTION
shell-quote lets you pass arbitrary strings through the shell so that they won't be changed by the shell. This lets you process commands
or files with embedded white space or shell globbing characters safely. Here are a few examples.
EXAMPLES
ssh preserving args
When running a remote command with ssh, ssh doesn't preserve the separate arguments it receives. It just joins them with spaces and
passes them to "$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)