Progression Handler: Progress Reported as the Size of a File on the File System

handler_filesize(
  file = "default.progress",
  intrusiveness = getOption("progressr.intrusiveness.file", 5),
  target = "file",
  enable = getOption("progressr.enable", TRUE),
  ...
)

Arguments

file

(character) A filename.

intrusiveness

(numeric) A non-negative scalar on how intrusive (disruptive) the reporter to the user.

target

(character vector) Specifies where progression updates are rendered.

enable

(logical) If FALSE, then progress is not reported.

...

Additional arguments passed to make_progression_handler().

Details

This progression handler reports progress by updating the size of a file on the file system. This provides a convenient way for an R script running in batch mode to report on the progress such that the user can peek at the file size (by default in 0-100 bytes) to assess the amount of the progress made, e.g. ls -l -- *.progress. If the *.progress file is accessible via for instance SSH, SFTP, FTPS, HTTPS, etc., then progress can be assessed from a remote location.

Examples

if (FALSE) {
handlers(handler_filesize(file = "myscript.progress"))
with_progress(y <- slow_sum(1:100))
print(y)
}