Skip to main content

UNIX : Awk example to strip character of word


The below program will read all the first character of a line and join it together.



#!/bin/bash

F="file.txt"

for i in $(cat $F)
do
          echo $i | awk -F"_" 'BEGIN{ st="" } 
          { for( i=1; i<=NF; i++ )
          { st=st""toupper(substr($i,1,1)) }
          }
           END{ print st }'
done

The program will read a file with "_"(underscore) delimited content. Then all the first character of the line will be striped and joined together.

Eg:

File name : Word_File_Created_by_John"

Output : WFCBJ

Note then small case is also turned to upper case.

The below awk functions are used in this program

toupper() - This will convert the string to upper case
substr() - This will strip the specific character(s) from the string




Comments

Popular posts from this blog

UNIX : How to ignore lines with certain names

Sometimes we need to ignore multiple lines with certain words and get the list out of the file. usually it will be a log file to read . The below grep command can be used to ignore multiple words present in a text file. Lets say the file contain $ cat list.txt apple orange apple banana papaya Now we need to ignore line with orange , banana and papaya . So we can use the below grep command. $ cat list.txt | grep -Ev "orange|banana|papaya" apple apple It will ignore lines with the words in -v part of grep.

UNIX : unpack and pack using tar

Tarball or tar is a utility in linux to unpack or pack the files. Lets say we have a file name hello.tar.gz which is packed and compressed. To unpack the file use the below command > tar xvzf hello.tar.gz This is unpack the compressed tarball file to the directory hello in current location. To pack a list of files to a compressed tarball file , we can follow the below steps. Let say we have the following list of files in Hello directory. > cd Hello > ls helloworld.py README.txt Move back to parent directory and give the below command. > cd .. > tar zcvf hello.tar.gz Hello This will create the compressed tar file in the current location