Posix Spawn

:::info[Note] This is a point-in-time snapshot of the API documentation from January 2026. Going forward, we will not be maintaining a public copy of these references, and recommend users to refer to the built-in signature helpers available in the Hack LSP instead for complete and up-to-date information. :::

namespace HH\Lib\OS;

function posix_spawn(
  string $file,
  posix_spawn_file_actions_t $file_actions,
  posix_spawnattr_t $attributes,
  vec<string> $argv,
  vec<string> $envp,
): pid_t;

Parameters

• string $file
• posix_spawn_file_actions_t $file_actions
• posix_spawnattr_t $attributes
• vec<string> $argv
• vec<string> $envp

Returns

• pid_t