How does Unix shell read files by row and parse rows?

Read files by row:

Java code

1. While read myline
2. Do
3. Echo $ myline
4. Done </etc/passwd

This program is to put the input file/Etc/passwdOne output.

If we only need to output username and home directory, We need to parse the file.
Each row is roughly as follows, with the column separator: username in the first column and home directory in the sixth column.

Java code

1. Ecrane :! : 300801: 1: Eric Crane = ecrane@us.ibm.com:/home/ecrane:/usr/bin/KSh

We only need to print the two columns:

Java code

1. While read myline
2. Do
3. Echo $ myline | cut-D:-F1, 6
4. Done </etc/passwd

The program is very simple.-D: is to define the separator:,-F1, 6 is to specify the first and sixth columns of the operation.

Of course, there is another way to use the awk command:

Java code

1. While read myline
2. Do
3. Echo $ myline | awk-F: '{print $1, $6 }'
4. Done </etc/passwd