Hi MadeinGermany
I cannot use single quotes as there are several SQLs using string literals with single quotes within the su -c block that can cause the shell to get confused.
For eg: select to_char(sysdate,'DD/MM/YYYY HH24:MI:SS') from dual;
Thank you for pointing out the missing escape character for the second $counter variable
ongoto's suggestion of escaping the backtick seems to fix this issue. The following script has worked.
I need to check if it works in my real life script. THANK YOU BOTH VERY MUCH.
Code:
# cat realLife.sh
sudo su - appuser -c "
export counter=1
while true
do
if grep -iq BASKETBALL /tmp/somestring.txt
then
echo This loop iterated \$counter times before exiting..
break
fi
sleep 5
counter=\`expr \$counter + 1\`
done
"
Another question, is it possible to, in a for-loop incrementing until it reaches a certain number, to have it loop again without incrementing? Just have it drop what it is doing when it reaches this command and start again at the same number it was at? I know I could make a while loop and just... (0 Replies)
Hi All,
I amlearning UNIX scripting. I have a small query. I would be thankful if any one helps me out.
I have a below piece of code which delets the files. If file dosent have the permissions to delete a particular file I have used 2>>operator to track the error code.
But my objective is... (1 Reply)
I wonder how to stop further loop iterations when conditions gets false e.g.
This file.txt contains the following structure :
1
2
3
4
5
6
7
8
9
10
How to stop iteration when if statement gets false ?
for n in `cat file.txt`
do
if (( n<=5 )) (1 Reply)
question :how can i iterate to next item in for loop with the loop
e.g
for i in `cat abc.txt`
do
echo $i // this will display first line
i=$i+1; // this doesnt work for me.
echo $i; //this will display secound line
done
question: is my approach to manipulate text good?
I have... (3 Replies)
I have written the following script to update some Debian boxes.
#!/bin/bash
mxg_hosts_file="/etc/mxg/ssh-hosts"
while read line ; do
mxg_host="$(echo ${line} | awk -F":" '{print $1}')"
mxg_port="$(echo ${line} | awk -F":" '{print $2}')"
echo "Connecting and Upgrading... (3 Replies)
for VGLIST in `lsvg -o`
do
CLOSED_OUT=`echo $VGLIST | lsvg -l $VGLIST | awk '{print $6 " " $7}' | grep closed`
if ]; then
echo "Filesystems $CLOSED_OUT in VG that are in Closed status"
else
echo "\n Some message"
fi
Above Code is working fine, but echo "Filesystems $CLOSED_OUT... (8 Replies)
I have a script with logic like:
my_function()
{
if
mkdir $1
mkdir mydir_${2}
else
do something else
fi
}
read in list of items
while read list
do
my_function $list `date`
done
so basically it will make a directory for every name in the list and create a directory with the... (6 Replies)
I am trying to check multiple server's "uptime" in a loop over "ssh".
When I execute multiple ssh commands with hard coded servernames script is executing fine.
But when I pass server names using while loop, script is exiting after checking first server's status, why?
# serverList... (8 Replies)
Hello,
I have been stuck on this for some time and invested many hours trying to find a solution. I am trying to either loop through two variables or or two arrays and not sure how to do it. I am limited to ksh only, and don't have the ability to do a foreach, or for i AND for j etc...I... (19 Replies)
Hello,
I've written a script to automate encoding of all the MP4 files in a directory (incl. subdirectories). But unfortunately it's running for the first MP4 file only.
My machine details:
root@Ubuntu16:~# uname -a
Linux Ubuntu16 4.10.0-28-generic #32~16.04.2-Ubuntu SMP Thu Jul 20 10:19:48... (2 Replies)
Discussion started by: prvnrk
2 Replies
LEARN ABOUT DEBIAN
file::counterfile
CounterFile(3pm) User Contributed Perl Documentation CounterFile(3pm)NAME
File::CounterFile - Persistent counter class
SYNOPSIS
use File::CounterFile;
$c = File::CounterFile->new("COUNTER", "aa00");
$id = $c->inc;
open(F, ">F$id");
DESCRIPTION
This module implements a persistent counter class. Each counter is represented by a separate file in the file system. File locking is
applied, so multiple processes can attempt to access a counter simultaneously without risk of counter destruction.
You give the file name as the first parameter to the object constructor ("new"). The file is created if it does not exist.
If the file name does not start with "/" or ".", then it is interpreted as a file relative to $File::CounterFile::DEFAULT_DIR. The default
value for this variable is initialized from the environment variable "TMPDIR", or /usr/tmp if no environment variable is defined. You may
want to assign a different value to this variable before creating counters.
If you pass a second parameter to the constructor, it sets the initial value for a new counter. This parameter only takes effect when the
file is created (i.e. it does not exist before the call).
When you call the "inc()" method, you increment the counter value by one. When you call "dec()", the counter value is decremented. In both
cases the new value is returned. The "dec()" method only works for numerical counters (digits only).
You can peek at the value of the counter (without incrementing it) by using the "value()" method.
The counter can be locked and unlocked with the "lock()" and "unlock()" methods. Incrementing and value retrieval are faster when the
counter is locked, because we do not have to update the counter file all the time. You can query whether the counter is locked with the
"locked()" method.
There is also an operator overloading interface to the File::CounterFile object. This means that you can use the "++" operator for
incrementing and the "--" operator for decrementing the counter, and you can interpolate counters directly into strings.
COPYRIGHT
Copyright (c) 1995-1998,2002,2003 Gisle Aas. All rights reserved.
This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself.
AUTHOR
Gisle Aas <gisle@aas.no>
perl v5.10.0 2004-01-23 CounterFile(3pm)
01-06-2015
