To read a file line by line in a Ksh (Korn shell) script on Unix, you can use a while loop with the read command. Here’s an example script that demonstrates how to read a file line by line in Ksh:
while read line
do
echo $line
done < file.txt
In this script, the while loop reads the file file.txt line by line using the read command. Each line is stored in the variable line, and the echo command is used to print the line to the console.
You can replace the echo command with any other command that you want to perform on each line of the file. For example, you could use the grep command to search for a specific pattern in each line:
while read line
do
if [[ $line =~ "pattern" ]]
then
echo $line
fi
done < file.txt
In this example, the if statement checks whether the line contains the string “pattern”, and if it does, the echo command is used to print the line to the console.
Note that in Ksh, you can use the [[ ... ]] syntax for more advanced conditional statements, such as regular expression matches with the =~ operator. If you need to use a single [ ... ] bracket for compatibility with other shells, you can do so, but some of the more advanced features may not be available.