set.file.extension: Determine or modify file name extensions
Description
Function get.file.extension determines the file extension, set.file.extension changes it, and default.file.extension changes it only if it is not already specified.
default.file.extension(filename, extension, force = FALSE)
Value
character vector of same length as filename
Arguments
filename
character vector: file name(s), possibly including paths and extensions; a file name ending with a "." is interpreted as having extension "", while a file name that doesn't contain a "." is interpreted has having no extension.
extension
character string: file extension, without the dot
fsep
character: separator between paths
force
logical argument to default.file.extension: force the file extension to be extension (same result as set.file.extension), or only set it to extension if it has not been specified?