I have the following command to gather all files in a folder and concatenate them....but what is held in the variable is only the file names and not the directory. How can I add 'colid-data/' to each of the files for cat to us?
cat $(ls -t colid-data) > catfiles.txt
List the filenames, not the directory.
cat $(ls -t colid-data/*) > catfiles.txt
Note that this will not work if any of the filenames contain whitespace. See Why not parse ls? for better alternatives.
If you want to concatenate them in date order, consider using zsh:
cat colid-data/*(.om) >catfiles.txt
That would concatenate all regular files only, in order of most recently modified first.
From bash, you could do this with
zsh -c 'cat colid-data/*(.om)' >catfiles.txt
If the ordering of the files is not important (and if there's only regular files in the directory, no subdirectories), just use
cat colid-data/* >catfiles.txt
All of these variations would work with filenames containing spaces, tabs and newlines, since the list of pathnames returned by a filename globbing pattern is not split into further words (which the result of an unquoted command substitution is).
