package spawn

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in-package search v0.2.0

Spawning sub-processes

Install

dune-project

Dependency

github.com Edit opam file Versions (12)

Authors

J

Jane Street Group, LLC

Maintainers

J

Jane Street developers

Sources

spawn-v0.11.0.tar.gz

sha256=f814d9c75e6c67627d16f2cbcb502be06d81d9b93ade9725d40fac492956097b

md5=85aa8d09cb50f80a9603dac4af333032

doc/spawn/Spawn/index.html

Module `Spawn`Source

Mini spawn library

Note: on Unix, spawn uses vfork by default. It has been tested, but if you believe this is causing a problem in your application, you can change this default at runtime by setting the environment variable SPAWN_USE_FORK.

Sourcemodule Working_dir : sig ... end

Sourcemodule Unix_backend : sig ... end

Source

val spawn : 
  ?env:string list ->
  ?cwd:Working_dir.t ->
  prog:string ->
  argv:string list ->
  ?stdin:Unix.file_descr ->
  ?stdout:Unix.file_descr ->
  ?stderr:Unix.file_descr ->
  ?unix_backend:Unix_backend.t ->
  unit ->
  int

Spawn a sub-command and return its PID. This function is low-level and should be used to build higher-level APIs.

In case of errors, it raises Unix.Unix_error.

Binary

prog is not searched in PATH. It is up to the caller to do the path resolution before calling this function. Note that there is no special treatment of executable text files without a proper #!. The execvp function from the C library calls /bin/sh in this case to imitate the behaviors of a shell but this function doesn't.

Environment

env must be a list of strings of the form "KEY=VALUE". It represents the environment in which the sub-process is executed. If not specified, the environment from the process calling this function is used.

Working directory

cwd describes what the current working directory of the sub-process should be. It defaults to Inherit. It is an error to pass Fd _ on Windows.

Standard input/outputs

stdin, stdout and stderr are the file descriptors used as standard input, output and error output of the sub-process. When not specified, they default to the ones from the calling process.

Signals

On Unix, the sub-process will have all its signals unblocked.

Implementation

unix_backend describes what backend to use on Unix. If set to Default, vfork is used unless the environment variable SPAWN_USE_FORK is set. On Windows, CreateProcess is used.