package spawn
Install
Dune Dependency
Authors
Maintainers
Sources
sha256=555fd0e7b0033e2274f528c74a4c3c0f50035c9c9e5ef9966044a99680ebffdf
md5=07c58bf2cc140cf44cacb10b9f2803e4
Description
Spawn is a small library exposing only one functionality: spawning sub-process.
It has three main goals:
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provide missing features of Unix.create_process such as providing a working directory
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provide better errors when a system call fails in the sub-process. For instance if a command is not found, you get a proper [Unix.Unix_error] exception
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improve performances by using vfork when available. It is often claimed that nowadays fork is as fast as vfork, however in practice fork takes time proportional to the process memory while vfork is constant time. In application using a lot of memory, vfork can be thousands of times faster than fork.
Published: 30 Mar 2018
README
SPAWN - spawning system process
Spawn is a small library exposing only one function: Spawn.spawn. Its purpose is to start command in the background. Spawn aims to provide a few missing features of Unix.create_process such as providing a working directory as well as improving error reporting and performance.
Errors such as directory or program not found are properly reported as Unix.Unix_error exceptions, on both Unix and Windows.
On Unix, Spawn uses vfork by default as it is often a lot faster than fork. There is a benchmark comparing Spawn.spawn to Unix.create_process in spawn-lib/bench. If you don't trust vfork, you can set the environment variable SPAWN_USE_FORK to make Spawn use fork instead.