C shell read line from file

File reading problem via shell script. Content of data. Reading file names from a file and executing the relative file from shell script. Hi How can i dynamically read files names from a list file and execute them from a single shell script. Please help its urgent Thanks in Advance 4 Replies.

RedHat Commands. OpenSolaris Commands. Linux Commands. SunOS Commands. FreeBSD Commands. Full Man Repository. Advanced Search. Contact Us. Forum Rules. Mark Forums Read. Thread Tools. View Public Profile for paruthiveeran. Find all posts by paruthiveeran. If the data in the file is huge, we would prefer going through the file line by line, in case it has a smaller number of words we can prefer going either word by word or character by character depending on the usability.

In most of the common scenarios, it is preferred to read line by line. Here we will see what kind of loops can be used for reading a file. There are eventually 2 loops through which it is possible to read a file. The concepts of loop are to implement these repetitive task through code and create powerful constructs through codes without any human intervention. In the for loop, the initialization, condition check all happens in the syntax of the for loop itself.

In the while loop, if we have to read a file, we would need to use a keyword read and hence this while is known as read while loop.

The main charismatic property is the ability to read line by line when you use the keyword read. The initialization is outside the while loop and that is the point of difference between for loop and read while loop. Both these loops are used keeping in mind the usability, and comfortableness of a developer to use any of the loops. Also one needs to make sure that an empty line is present in the end of the file. IFS is nothing but an internal field separator which is used with while loop to split the words and line based on its value.

If the file is available in the specified location then while loop will read the file line by line and print the file content. How to read each line of a file using a Shell script loop For example, you can process the data with csvkit to turn it into a JSON format, and then do more advanced work with a tool like jq a lightweight and flexible command-line JSON processor. Reading file line by line in cshell.

Letting users decide what files to process is more flexible and more consistent with built-in Unix commands. Share: KSH read while loop syntax.