02-20-2012
@Scrutinizer that is an excellent post.
I knew about
:
But it goes on to read the whole file.
But this piece of brilliant code does not feature in any of the many "sed one-liners" lists which I have read and it does not read the whole file. Therefore it is quick.
This User Gave Thanks to methyl For This Post:
10 More Discussions You Might Find Interesting
1. UNIX for Dummies Questions & Answers
Hi all,
I need to know what command/s I can use to print lines from a file. I cannot do pattern matching, so grepping for a string is not possible. I'd like to say "print line 3" etc. Any ideas? Ta. (2 Replies)
Discussion started by: danhodges99
2 Replies
2. Shell Programming and Scripting
I have a file where each line is a stream of text as follows,
table1, select * from table1
table2, select * from table2
How do i loop through the file line by line? I have tried doing the following
for line in `cat file.txt`
do
echo $line
done
and ...
cat file.txt|while read line... (2 Replies)
Discussion started by: handak9
2 Replies
3. Shell Programming and Scripting
Hi friends
I need to get what ever line number i want
Supplier.profile
-----------------
SFTP/INVTRAN
SFTP/INVSNAP
GATEWAY/INVTRAN
GATEWAY/INVSNAP
----------------
exec 0<$Supplier.profile
while read LINE
do
echo $LINE (1 Reply)
Discussion started by: kittusri9
1 Replies
4. Shell Programming and Scripting
I need to print ist and last line of a file
My file having
abc
def
dfg
jkl
bnm
outout will be
abc
bnm
---------- Post updated at 11:24 PM ---------- Previous update was at 11:16 PM ----------
pls help me out. Can any one do this. (5 Replies)
Discussion started by: pritish.sas
5 Replies
5. Shell Programming and Scripting
I have a list of words, one word per line, LIST1.TXT that I want to check for in another file, PARAGRAPHS.TXT. If the line from LIST1.TXT is NOT in PARAGRAPHS.TXT I want to print it to screen. The keyword here is NOT. If the word from LIST1.TXT is NOT in the file PARAGRAPHS.TXT, then I want to... (7 Replies)
Discussion started by: ajp7701
7 Replies
6. Shell Programming and Scripting
I have a .csv file which is seperated with (;)
inputfile
---------
ZZZZ;AAAA;BBB;CCCC;DDD;EEE;
YYYY;BBBB;CCC;DDDD;EEE;FFF;
...
...
reading file line by line till end of file.
while reading each line output format should be .
i need to print only specific columns let say 5th... (2 Replies)
Discussion started by: rocking77
2 Replies
7. Shell Programming and Scripting
Hi Experts,
I am very new to scripting and have a prb since few days and it is urgent to solve so much appreciated if u help me.
i have 2 files
file1.txt
9647810043118
9647810043126
9647810043155
9647810043161
9647810043166
9647810043185
9647810043200
9647810043203
9647810043250... (22 Replies)
Discussion started by: mustafa.abdulsa
22 Replies
8. Shell Programming and Scripting
hi
# cat test.txt
Test
Date: 20131008 1515
--------------------------------------------------------------------------------------------------------------
Saxx = Proc_m0_s13 : 1640
Saxx = Proc_m0_s15 : 1791
Saxx = Proc_m0_s17 ... (2 Replies)
Discussion started by: justbow
2 Replies
9. UNIX for Beginners Questions & Answers
example of problem:
when I echo "$e" >> /home/cogiz/file.txt
result prints to file as:AA
BB
CC
I need it to save to file as this:AA BB CC
I know it's probably something really simple but any help would be greatly appreciated.
Thank You.
Cogiz (7 Replies)
Discussion started by: cogiz
7 Replies
10. UNIX for Beginners Questions & Answers
Hi All,
i want to write a shell script read below file line by line and want to exclude the lines which contains empty value for MOUNTPOINT field.
i am using centos 7 Operating system.
want to read below file.
# cat /tmp/d5
NAME="/dev/sda" TYPE="disk" SIZE="60G" OWNER="root"... (4 Replies)
Discussion started by: balu1234
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)