A simple and fast bash script for GNU systems to merge multiple files in a directory to a single file. This can come in handy if you need to merge multiple CSV files to a single csv file or multiple TEXT files to a single text file.

Suppose you have a set of txt files in a directory called ~/myfiles

~/
 └─── myfiles
     │   test1.txt
     │   test2.txt
     │   test3.txt
     │   test4.txt
     │   other.txt
     └─── ...

To merge all files with name starting test to a output file called result.txt

/bin/bash file-merge-script.sh -d ~/myfiles -p 'test' -o 'result.txt'

• -d : (required) directory containing files
• -p : (optional) input file prefix | default - all files in the given directory
• -o : (optional) output file name | default - 'output.txt'
• -s : (optional) line to start from matching files | default - 1
• -f : (optional) line to start from first matching file | default - 1
• -r : (optional) delete prefix files after output file created
• -l : (optional) log prefix

• Merge multiple csv files with headers from the 1st file and ignore headers from the rest of the files

/bin/bash file-merge-script.sh -d ~/myfiles -p 'test' -o 'result.csv' -f 1 -s 2

In above command -f 1 gets all content (from line 1) of first matching csv file and -s 2 gets all matching file contents from line 2.