UNIX : Using IF in bash

The IF statement is used to test the given condition and based on the truth value of that the expression the statement followed is executed.Otherwise the else part is executed.

The basic structure of if is as follows.

If [[ expression ]];then

expression

elif [[expression ]];then

expression

else

expression

1) Integer comparison

2) String comparison

3) Using multiple conditions in IF statement

4) Compare regular expression in bash

Comments

UNIX : How to get record count from zipped file

Sometimes we may need to get records count from file . For that we can use wc -l , command with file name. In some situation the file will be in compressed format . wc -l will not directly work with zipped files . In this case we can do zcat the file and pipe the word count command with it. Example : Let say we have a file cricketData.dat.gz To get word count from the file use : zcat cricketData.dat.gz | wc -l This will give the record count.

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.

Scala

Scala is a object oriented functional type programing language. All variables declared in scala is considered as objects.

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