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Process view

Source: R/widget-process.R
process_view.Rd

Runs an external program (without a shell) and shows its output in a scrolling log: standard output as normal lines and standard error in the error colour, under a one-line status. The process starts when the view is mounted (or call $start()), is cancelled when the view is removed or the app exits, and sends "process.finished" (status, state) when it ends. Ctrl+X cancels it and Ctrl+R restarts it while the view has focus. Experimental.

Usage

process_view(
  command,
  args = character(),
  wd = NULL,
  env = NULL,
  timeout = NULL,
  autostart = TRUE,
  max_lines = 2000L,
  id = NULL,
  classes = NULL,
  style = NULL
)

Arguments

command

The program (a path or a name on the PATH).

args

Arguments, one element each; never interpreted by a shell.

wd

Working directory (NULL: current).

env

Named character vector of extra environment variables.

timeout

Seconds before the process is stopped (NULL: no limit).

autostart

Start when mounted?

max_lines

Output lines kept.

id, classes, style

Common widget arguments.

Value

A ProcessView widget with $start(), $cancel(), $restart(), $running, $output and $worker.

Examples

pv <- process_view(file.path(R.home("bin"), "Rscript"), c("-e", "cat('hi\\n')"),
                   autostart = FALSE)
pv$running
#> [1] FALSE