| files {base} | R Documentation |
These functions provide a low-level interface to the computer's file system.
file.create(...) file.exists(...) file.remove(...) file.append(file1, file2) file.copy(from, to, overwrite = FALSE) dir.create(path) basename(path) dirname(path) path.expand(path)
..., file1, file2, from, to, path |
character vectors, containing file names. |
overwrite |
logical; should the destination files be overwritten? |
The ... arguments are concatenated to form one character
string: you can specify the files separately or as one vector.
file.create creates files with the given names if they
do not already exist and truncates them if they do.
It returns a logical vector indicating the success or failure
of the operation for each file.
file.exists returns a logical vector indicating whether
the files named by its argument exist.
file.remove attempts to remove the files named in its
argument. It returns a logical vector indicating whether or
not it succeeded in removing each file.
file.append attempts to append the files named by its
second argument to those named by its first. The R subscript
recycling rule is used to align names given in vectors
of different lengths.
file.copy works in a similar way to file.append but with
the arguments in the natural order for copying. Copying to existing
destination files is skipped unless overwrite = TRUE.
The to argument can specify a single existing directory.
dir.create creates the last element of the path. It returns a
logical, true for success.
basename removes all of the path up to the last path separator
(if any).
dirname returns the part of the path up to (but
excluding) the last path separator, or "." if there is no path
separator. Tilde expansion is done: see the description for
path.expand below.
In both basename and dirname trailing file separators
are removed before dissecting the path, and for dirname any
trailing file separators are removed from the result.
path.expand expands path(s) by replacing a leading tilde by the
user's home directory (if defined on that platform).
On some Unix versions, a leading ~user will expand to
the home directory of user, but not on Unix versions without
readline installed.
Ross Ihaka, Brian Ripley
file.info, file.access,
file.show, list.files,
unlink.
cat("file A\n", file="A")
cat("file B\n", file="B")
file.append("A", "B")
file.create("A")
file.append("A", rep("B", 10))
if(interactive()) file.show("A")
file.copy("A", "C")
dir.create("tmp")
file.copy(c("A", "B"), "tmp")
unlink("tmp", recursive=TRUE)
file.remove("A", "B", "C")
basename(file.path("","p1","p2","p3","filename"))
dirname(file.path("","p1","p2","p3","filename"))
path.expand("~/foo")