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Linux dd Command Show Progress Copy Bar With Status

I'm using dd command for block level copy and just found out that there's no built in way to check the progress. How do I use the Linux or Unix dd command while coping /dev/sda to /deb/sdb and display a progress bar when data goes through a pipe?
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HowTo: Use Grep Command In Unix / Linux To Search Subdirectories

I would like to search and find all files which contain a word called "main()" for all directories located in $HOME/project/school. How do I use the grep command to find text including all subdirs under Unix or Linux operating systems?
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HowTo: Revoke OpenSSH Keys and Disable User Access

Many users are using ssh to log into a remote machine and append the indicated identity file to machine's ~/.ssh/authorized_keys file. I recently moved one of my server, and I would like to revoke openssh keys and disable user access under Linux operating systems. How do I revoke OpenSSH keys under Unix or Linux operating systems?
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Linux / Unix: sed Command Print Only Matching Lines

I see many examples and man pages on how to do operations like search-and-replace using sed. But, I want to match a given string or a regular pattern expression and display on the screen. How do I print lines with matching pattern using sed command only under Unix like operating systems?
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Unix / Linux: Maximum Character Length of Arguments In a Shell Command

What is the maximum character length of arguments in a shell command? How do I find out the maximum length of arguments for a new process under Linux or Unix like operating systems?
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Linux / Unix: Find Out DNS Server IP Address / Names

How do I find out my DNS server IP address assiged my my ISP under Unix or Linux operating system using command prompt? How do I find preferred dns server under Debian / Ubuntu / Fedora Linux desktop system?
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awk: warning: escape sequence '\<' treated as plain '>'

I'm trying to match words using GNU awk command and getting the following error:

echo 'foo bar this that blah' | awk '{gsub("\<regex-word\>", "NEW-WORD");print}'

But getting the following warning on screen and it is not working:
awk: warning: escape sequence `\< ' treated as plain `<' awk: warning: escape sequence `\>' treated as plain `>'

How do I fix this problem under Unix like operating systems?
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Linux / Unix rsync: Delete Source File After Transfer

I would like to move all desktop:~/Downloads/*.avi files from my desktop to laptop:~/Download/ using rsync. How do I delete source file after successful transfer is done using rsync command under BSD/Unix/Linux/Apple OS X operating systems?
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Bash History: Correct / Repeat The Last Command With a Substitution

I often type the wrong command as follows under Linux bash shell:
rsync -av dir1 user@server1.cyberciti.biz:/path/to/dir1
cp -av file1*.txt file2*.txt /path/to/dest

I need to correct those command as follows:

rsync -av dir5 user@server1.cyberciti.biz:/path/to/dir1
cp -av delta1*.txt delta2*.txt /path/to/dest

How do I replace dir1 with dir5 or file with delta and repeat the last command under bash shell?
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HowTo: grep Text Between Two Words in Unix / Linux

I got over 100s of HTML files in the following format:

 <title>Statistics for ABC LTD - January 2007 - Rang IDXYZZAZZZZ</title>
<body BGCOLOR="#E8E8E8" TEXT="#000000" LINK="#0000FF" VLINK="#FF0000">
<h2>Statistics for ABC LTF</h2>
Summary Period: January 2007<br />
Generated 01-Feb-2007 06:40 CET<br />
<hr />
<font SIZE="-1"></font></p></center><pre>
my data 1
my data 2
my data 3
my data 10000
my data N times

Generated by MyAppDbStatsWriter (UNIX) version 1.9b2

How do I extract text between two words (<PRE> and </PRE>) in unix or linux using grep command?
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