Temporary files and directories

Temporarily create a file or directory, which will automatically deleted once you're finished with it.

Usage

with_tempfile(
  new,
  code,
  envir = parent.frame(),
  .local_envir = parent.frame(),
  pattern = "file",
  tmpdir = tempdir(),
  fileext = ""
)

local_tempfile(
  new = NULL,
  lines = NULL,
  envir = parent.frame(),
  .local_envir = parent.frame(),
  pattern = "file",
  tmpdir = tempdir(),
  fileext = ""
)

with_tempdir(
  code,
  clean = TRUE,
  pattern = "file",
  tmpdir = tempdir(),
  fileext = ""
)

local_tempdir(
  pattern = "file",
  tmpdir = tempdir(),
  fileext = "",
  .local_envir = parent.frame(),
  clean = TRUE
)

Arguments

new

[character vector]
(Deprecated for local_tempfile()) Names of temporary file handles to create.

code

[any]
Code to execute in the temporary environment

envir

[environment]
Deprecated in favor of .local_envir.

.local_envir

[environment]
The environment to use for scoping.

pattern

a non-empty character vector giving the initial part of the name.

tmpdir

a non-empty character vector giving the directory name

fileext

a non-empty character vector giving the file extension

lines

Optionally, supply a character vector of lines to be written to path. This is useful if you want to seed the file with some default content.

clean

[logical(1)]
A logical indicating if the temporary directory should be deleted after use (TRUE, default) or left alone (FALSE).

Value

[any]
The results of the evaluation of the code

argument.

See also

withr for examples

Examples

# local_tempfile() is the easiest to use because it returns a path
local({
  path1 <<- local_tempfile(lines = c("x,y", "1,2"))
  readLines(path1)
})
#> [1] "x,y" "1,2"
# the file is deleted automatically
file.exists(path1)
#> [1] FALSE

# with_tempfile() is a bit trickier; the first argument gives the name
# of a variable that will contain the path:
with_tempfile("path2", {
  print(path2)
  write.csv(iris, path2)
  file.size(path2)
})
#> [1] "/tmp/RtmpP0KrJB/file183f7369417e"
#> [1] 4821

# Note that this variable is only available in the scope of with_tempfile
try(path2)
#> Error in eval(expr, envir, enclos) : object 'path2' not found