Sys.glob {base} | R Documentation |
Function to do wildcard expansion (also known as ‘globbing’) on file paths.
Not all platforms support this.
Sys.glob(paths, dirmark = FALSE)
paths |
character vector of patterns for relative or absolute filepaths. |
dirmark |
logical: should matches to directories from patterns
that do not already end in /
have a slash appended? May not be supported on all platforms. |
This expands wildcards in file paths. For precise details, see your
system's documentation on the glob
system call. There is a
POSIX 1003.2 standard (see
http://www.opengroup.org/onlinepubs/009695399/functions/glob.html)
but some OSes will go beyond this (in particular some BSD-based OSes also
do tilde expansion, see path.expand
).
All systems should interpret *
(match one of more characters),
?
(match a single character) and [
(begin a character
class or range). If a filename starts with .
this must be
matched explicitly. Normally paths ending in /
will be
accepted and matched only to directories.
The rest of these details are indicative (and based on the POSIX standard).
[
begins a character class. If the first character in
[...]
is not !
, this is a character class which matches
a single character against any of the characters specified. The class
cannot be empty, so ]
can be included provided it is first. If
the first character is !
, the character class matches a single
character which is none of the none of the specified
characters.
Character classes can include ranges such as [A-Z]
: include
-
as a character by having it first or last in a class. (The
interpretation of ranges should be locale-specific.)
One can remove the special meaning of ?
, *
and
[
by preceding them by a backslash (except within a
character class).
A character vector of matched file paths. The order is
system-specific (but in the order of the elements of paths
): it
is normally collated in the current locale or in byte (ASCII) order.
Directory errors are normally ignored, so the matches are to
accessible file paths (but not necessarily accessible files).
On platforms which do not have the glob
system call,
paths
is returned unchanged.
Quotes for handling backslashes in character strings.
## Not run: Sys.glob(file.path(R.home(), "library", "*", "R", "*.rdx")) ## End(Not run)