Visit Our UNIX and Linux User Community


Read a file line by line


 
Thread Tools Search this Thread
Top Forums Shell Programming and Scripting Read a file line by line
# 1  
Old 07-24-2009
Read a file line by line

Hi everybody,

I have a config file what looks like this

Code:
# name name
#host TYPE-IFTYPE-user{
#       hardware ethernet 00:00:00:00:00:00;
#       fixed-address 0.0.0.0;
#}

## unknown
#host TYPE-IFTYPE-USER{
#       hardware ethernet 00:00:00:00:00:00;
#       fixed-address 0.0.0.0;
#}

# name name
#host TYPE-IFTYPE-user{
#       hardware ethernet 00:00:00:00:00:00;
#       fixed-address 0.0.0.0;
#}

## unknown
#host TYPE-IFTYPE-USER{
#       hardware ethernet 00:00:00:00:00:00;
#       fixed-address 0.0.0.0;
#}

so what i want is to write a script what reads the config file line by line and print only the unknown patterns and the following three lines into a text file.

I dont know how to tell the script read from here to here begin at every unknown pattern.

Please help me

thanx
# 2  
Old 07-24-2009
Code:
grep -A3 'unknown' cfgfile

# 3  
Old 07-24-2009
This works nice!!!Smilie

Thank you very much!!!
# 4  
Old 07-24-2009
Code:
 sed -n '/unknown/{N;N;N;p;}' file

# 5  
Old 07-24-2009
works too!!!

thanks

Previous Thread | Next Thread
Test Your Knowledge in Computers #612
Difficulty: Medium
In Python, they are five numeric types - integers, long integers, floating point, infinite, and complex numbers.
True or False?

10 More Discussions You Might Find Interesting

1. Shell Programming and Scripting

With script bash, read file line per line starting at the end

Hello, I'm works on Ubuntu server My goal : I would like to read file line per line, but i want to started at the end of file. Currently, I use instructions : while read line; do COMMAND done < /var/log/apache2/access.log But, the first line, i don't want this. The file is long... (5 Replies)
Discussion started by: Fuziion
5 Replies

2. Shell Programming and Scripting

How to read file line by line and compare subset of 1st line with 2nd?

Hi all, I have a log file say Test.log that gets updated continuously and it has data in pipe separated format. A sample log file would look like: <date1>|<data1>|<url1>|<result1> <date2>|<data2>|<url2>|<result2> <date3>|<data3>|<url3>|<result3> <date4>|<data4>|<url4>|<result4> What I... (3 Replies)
Discussion started by: pat_pramod
3 Replies

3. Shell Programming and Scripting

Bash script to read a file from particular line till required line and process

Hi All, Am trying to write wrapper shell/bash script on a utility tool for which i need to pass 2 files as arugment to execute utility tool. Wraper script am trying is to do with above metion 2 files. utility tool accepts : a. userinfo file : which contains username b. item file : which... (2 Replies)
Discussion started by: Optimus81
2 Replies

4. Shell Programming and Scripting

How to read a text file line by line and insert into a database table?

I have a test file that I want to read and insert only certain lines into the the table based on a filter. 1. Rread the log file 12 Hours back Getdate() -12 Hours 2. Extract the following information on for lines that say "DUMP is complete" A. Date B. Database Name C.... (2 Replies)
Discussion started by: JolietJake
2 Replies

5. Shell Programming and Scripting

Need a program that read a file line by line and prints out lines 1, 2 & 3 after an empty line...

Hello, I need a program that read a file line by line and prints out lines 1, 2 & 3 after an empty line... An example of entries in the file would be: SRVXPAPI001 ERRO JUN24 07:28:34 1775 REASON= 0000, PROCID= #E506 #1065: TPCIPPR, INDEX= 003F ... (8 Replies)
Discussion started by: Ferocci
8 Replies

6. Shell Programming and Scripting

how to read the contents of two files line by line and compare the line by line?

Hi All, I'm trying to figure out which are the trusted-ips and which are not using a script file.. I have a file named 'ip-list.txt' which contains some ip addresses and another file named 'trusted-ip-list.txt' which also contains some ip addresses. I want to read a line from... (4 Replies)
Discussion started by: mjavalkar
4 Replies

7. Shell Programming and Scripting

Shell script to read a text file line by line & process it...

Hi , I am trying to write an shell, which reads a text file (from a location) having a list of numbers of strictly 5 digits only ex: 33144 Now my script will check : 1) that each entry is only 5 digits & numeric only, no alphabets, & its not empty. 2)then it executes a shell script called... (8 Replies)
Discussion started by: new_to_shell
8 Replies

8. Shell Programming and Scripting

Read file line by line and process the line to generate another file

Hi, i have file which contains data as below(Only sample shown, it may contain more data similar to the one shown here) i need to read this file line by line and generate an output file like the one below i.e based on N value the number of MSISDNs will vary, if N=1 then the following... (14 Replies)
Discussion started by: aemunathan
14 Replies

9. Shell Programming and Scripting

bash: read file line by line (lines have '\0') - not full line has read???

I am using the while-loop to read a file. The file has lines with null-terminated strings (words, actually.) What I have by that reading - just a first word up to '\0'! I need to have whole string up to 'new line' - (LF, 10#10, 16#A) What I am doing wrong? #make file 'grb' with... (6 Replies)
Discussion started by: alex_5161
6 Replies

10. Shell Programming and Scripting

shell script to read a line in gps receiver log file and append that line to new file

Hi, I have gps receiver log..its giving readings .like below Trying 127.0.0.1... Connected to localhost. Escape character is '^]'. GPSD,R=1 $GPGSV,3,1,11,08,16,328,40,11,36,127,00,28,33,283,39,20,11,165,00*71... (3 Replies)
Discussion started by: gudivada213
3 Replies

Featured Tech Videos