Suppose we have a file contains the following information, termed input_file:

A       0

B       1

C       2

 

1. Read file one per line

(1):

while read line

do

        printf "$linen"

done <data

 

(2):

exec 6 <data                 # create a file handler

while read line 0<&6

do

        printf "$linen"

done

exec 6<&-                       # close file

 

 

2. Read and parse each line

while read x y

do

        echo $x $y

done <data

 

3.Read a file with user-specified delimiter

e.g. (file name: data) 

A:0

B:1

C:2

 

IFS=:                            # set delimiter, delimiter is white space by default

while read x y

do

        printf "$xt$yn"

done <data