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Shell Script for Extracting all the lines containing a particular string

This we can do in many ways using AWK, SED, PERL etc

Ex: Printing all the lines containing aaa in a file abc.txt
Using AWK:
awk '/aaa/{print}' abc.txt

Using PERL:
 perl -wn -e 'print if /aaa/' abc.txt


This can be written into another file by using redirection as
awk '/aaa/{print}' abc.txt  > tmp.txt

perl -wn -e 'print if /aaa/' abc.txt > tmp.txt


Regards
G K Reddy Chinthalapudi

Automating FTP Session through Shell Script

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Many times we save lot of time if we automate things.

Assume you want to put a fine named abcd.doc in server named www.myserver.com.
We will do as follows in terminal/command prompt

ftp www.myserver.com

Then it will ask for USERNAME and PASSWORD, if we enters correctly FTP session for us opened successfully. Then we can use ftp commands to put/get files to/from www.myserver.com. For putting abcd.doc we will use command put as follows

ftp>put abcd.doc

Then we will use bye to exit ftp session

ftp>bye



Automating above session through shell script
Assume user name is usermane and password password for logging into system www.myserver.com



user username password
put abcd.doc
close
bue
SCRIPT
exit 0


You can use IP address also instead of server name.


Automating FTP Session through Shell Script

Many times we save lot of time if we automate things.

Assume you want to put a fine named abcd.doc in server named www.myserver.com
We will do as follows in terminal/command prompt

ftp www.myserver.com

Then it will ask for USERNAME and PASSWORD, if we enters correctly FTP session for us opened successfully. Then we can use ftp commands to put/get files to/from www.myserver.com. For putting abcd.doc we will use command put as follows

ftp>put abcd.doc

Then we will use bye to exit ftp session

ftp>bye



Automating this session
Assume user name is usermane and password is password for logging into system www.myserver.com

ftp -n www.myserver.com <







Group Photos with Colleagues in C-Dot, Bangalore

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My Village(Bhaskar Nagar) Photos

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LAPD vs LAPDm(Technical)

Layer 2 Functionalities
Framing
Error detection & Correction
Multiplexing
Flow Controller

Framing Issues
LAPD uses HDLC frame format for framing.
Where as LAPDm uses synchronization scheme of radio interface to convey information on frame limits. LAPDm avoids using flags by ready-made blocks of the physical layer. LAPDm(LAPD modified) frame has a maximum length of 23 octets on all TCH channels and 21 octets on SACCH blocks(remaining 2 octets are for Timing Advance and Transmission Power Control). But the actual frame length is less than 23/21 octets, so Length Indicator(LI) is included in each frame to identify the length of the frame.

Segmentation & Reassembly
There is no need of segmentation & Reassembly in LAPD(the length of the Abis LAPD frame is 264 octets excluding flags, which corresponds to 260 octets of upper layer information).
Where as LAPD requires segmentation& reassembly because maximum frame length of 21 or 23 octets is not sufficient for most signalling needs.

Err…

LAPD vs LAPDm

Layer 2 Functionalities
Framing
Error detection & Correction
Multiplexing
Flow Controller

Framing Issues
LAPD uses HDLC frame format for framing.
Where as LAPDm uses synchronization scheme of radio interface to convey information on frame limits. LAPDm avoids using flags by ready-made blocks of the physical layer. LAPDm(LAPD modified) frame has a maximum length of 23 octets on all TCH channels and 21 octets on SACCH blocks(remaining 2 octets are for Timing Advance and Transmission Power Control). But the actual frame length is less than 23/21 octets, so Length Indicator(LI) is included in each frame to identify the length of the frame.

Segmentation & Reassembly
There is no need of segmentation & Reassembly in LAPD(the length of the Abis LAPD frame is 264 octets excluding flags, which corresponds to 260 octets of upper layer information).
Where as LAPD requires segmentation& reassembly because maximum frame length of 21 or 23 octets is not sufficient for most signalling needs.

Er…