systemFile {svMisc}R Documentation

Get a system file or directory

Description

Get system files or directories, in R subdirectories, in package subdirectories, or elsewhere on the disk (including executables that are accessible on the search path).

Usage

systemFile(..., exec = FALSE, package = NULL, lib.loc = NULL)
systemDir(..., exec = FALSE, package = NULL, lib.loc = NULL)

Arguments

...

one or several executables if exec = TRUE, or subpath to a file or dir in a package directory if package != NULL, or a list of path and subpaths for testing the existence of a file on disk, or a list of directory components to retrieve in 'temp', 'sysTemp', 'user', 'home', 'bin', 'doc', 'etc' and/or 'share' to retrieve special system directories.

exec

if TRUE (default) search for executables on the search path. It superseedes all other arguments.

package

the name of one package to look for files or subdirs in its main directory (use exec = FALSE to search inside package dirs).

lib.loc

a character vector with path names of R libraries or NULL (search all currently known libraries in this case).

Value

A string with the path to the directories or files, or "" if they are not found, or of the wrong type (a dir for systemFile() or or a file for systemDir()).

Note

These function aggregate the features of several R functions in package base: system.file(), R.home(), tempdir(), Sys.which(), and aim to provide a unified and convenient single interface to all of them. We make sure also to check that returned components are respectively directories and files for systemDir() and systemFile().

Author(s)

Philippe Grosjean <phgrosjean@sciviews.org>

See Also

fileEdit, file.path, file.exists

Examples

systemFile("INDEX", package = "base")
systemFile("help", "AnIndex", package = "splines")
systemFile(package = "base")  # This is a dir, not a file!
systemFile("zip", exec = TRUE)
systemFile("ftp", "ping", "zip", "nonexistingexe", exec = TRUE)
systemDir("temp")             # The R temporary directory
systemDir("sysTemp")          # The system temporary directory
systemDir("user")             # The user directory
systemDir("home", "bin", "doc", "etc", "share")  # Various R dirs
systemDir("zip", exec = TRUE) # Look for the dir of an executable
systemDir("ftp", "ping", "zip", "nonexistingexe", exec = TRUE)
systemDir(package = "base")   # The root of the 'base' package
systemDir(package = "stats")  # The root of package 'stats'
systemDir("INDEX", package = "stats") # This is a file, not a dir!
systemDir("help", package = "splines")
[Package svMisc version 0.9-70 Index]