Examples for 'processx::poll'

### ** Examples

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if (FALSE) (if (getRversion() >= "3.4") withAutoprint else force)({ # examplesIf
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# Different commands to run for windows and unix
cmd1 <- switch(
  .Platform$OS.type,
  "unix" = c("sh", "-c", "sleep 1; ls"),
  c("cmd", "/c", "ping -n 2 127.0.0.1 && dir /b")
)
cmd2 <- switch(
  .Platform$OS.type,
  "unix" = c("sh", "-c", "sleep 2; ls 1>&2"),
  c("cmd", "/c", "ping -n 2 127.0.0.1 && dir /b 1>&2")
)

## Run them. p1 writes to stdout, p2 to stderr, after some sleep
p1 <- process$new(cmd1[1], cmd1[-1], stdout = "|")
p2 <- process$new(cmd2[1], cmd2[-1], stderr = "|")

## Nothing to read initially
poll(list(p1 = p1, p2 = p2), 0)

## Wait until p1 finishes. Now p1 has some output
p1$wait()
poll(list(p1 = p1, p2 = p2), -1)

## Close p1's connection, p2 will have output on stderr, eventually
close(p1$get_output_connection())
poll(list(p1 = p1, p2 = p2), -1)

## Close p2's connection as well, no nothing to poll
close(p2$get_error_connection())
poll(list(p1 = p1, p2 = p2), 0)
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}) # examplesIf
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