files: Expand a file template into a list of files

Package: system

Usage

files template

Parameters

template

A file name template specifying the set of files to be listed.

sort = "yes"

Sort the file list.

Description

Files lists all files matching the given template. The existence of the listed files is checked only if pattern matching is used, hence files may also be used to parse a comma delimited list of strings which are not necessarily filenames. Files performs the same function as "dir l+" but is simpler and more convenient to use when generating file lists.

The files task and all other tasks which operate upon groups of files use the file template facility to specify the set of files to be operated upon. This should not be confused with the image template facility, used by tasks which operate upon sets of images and which is documented in the manual page for the sections task.

Pattern matching in a file template is provided by the usual pattern matching meta-characters "*?[]", documented in the CL User's Guide. Pattern matching is used to select files from one or more directories. In addition, the filename template notation provides two operators for generating new filenames from the matched filenames. These are the concatenation operator "//", and the string substitution operator "%chars%newchars%". The concatenation operator concatenates either a prefix to a filename, or a suffix to the root of a filename. The string substitution operator uses the "chars" to match filenames, and then replaces the "chars" by the "newchars" to generate the final output filename. Either string may be null length to insert into or delete characters from a filename.

Examples

1. Generate a single column list of files in the current directory, sorted in ASCII collating sequence.

cl> files

2. Generate an unsorted single column list of files in logical directory "lib$". Each entry in the output list is of the form "lib$...".

cl> files lib$ sort-

3. Generate a file list to be used to make a set of new files. The new file names will be the old file names with "_1" concatenated to the root, e.g., "root.x" would map to "root_1.x" and so on.

cl> files root.*//_1

4. Generate a file list similar to that in [3], adding a directory prefix to each filename.

cl> files dir$//root.*

5. Use string substitution to change the filename extension of a set of files to ".y".

cl> files root.%*%y%

See also

directory, pathnames, images.sections