Return the current working directory.
Return a simplified filename where the current path has been dropped if it occurs as a prefix of the given filename.
Return a simplified filename where any directory part has been dropped.
Return a simplified filename where a string has been dropped if it occurs as a prefix of the given filename.
Return a simplified filename where a string has been dropped if it occurs as a prefix of the given filename. The system separator character is also dropped if it occurs immediately after a non-empty prefix.
Return a temporary file name based on the current time.
Return a temporary file name based on the current time. Append the suffix (default: nothing).
Replace the extension of a filename with a new extension.
Replace the extension of a filename with a new extension. E.g. if the new extension is ".ll" and the filename is "foo.c", you get "foo.ll". If the filename has no extension then the new extension is just appended.
Support code for handling filenames.