process_view: Process view

In termr: Modern Reactive Terminal Applications with Data Workflows

Process view

Description

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

termr documentation built on Oct. 21, 2026, 5:13 p.m.