I had scanned a book and ran OCR to obtain several text files with the following pattern:

graph-1.txt, graph-2.txt, graph-3.txt, ....., graph-10.txt

I wanted to concatenate the text of all files into one. Googled on how to do it and found several useful links:

• Stack Overflow
• How-To Geek

One of the problems when concatenating file is to sort files and ls graph* -r -t helped. The -t option sorts files in descending order according to the modification time i.e. most recently modified file first. To reverse the sorting order use -r option. This information is provided by the How-To Geek link above.

To concatenate the contents of the file I took help by modifying one of the answers provided in response to the Stack Overflow question (see the link above).

The snippet I used is as follows:

for file in `ls graph* -t -r`; do cat "$file" >> allgraph.txt;done;

Which results in allgraph.txt containing the contents of all files.