ProcessClosedBeforeOwnedPipes

warning native on by default

Group: Probable bugs

Waiting for a child process while its owned pipes remain open can deadlock. Close or drain the pipes before waiting for process exit.

Example

<?php
$p=proc_open("worker",[1=>["pipe","w"]],$pipes);proc_close($p);

Reported:

• line 2: Close owned process pipes before waiting for process exit.

Detection

• Resolved proc_open declares at least one parent-owned pipe and assigns process local; proc_close occurs before all declared pipes are definitely closed/drained. Highlight proc_close; unknown descriptor shape excluded.
• The initial supported proof is an immediately preceding local assignment from proc_open, with explicit owned pipe descriptors and no intervening statements.
• Resolve builtin functions, classes, constants and methods; user-defined lookalikes are excluded. Follow only bounded local proof in one lexical scope.
• Emit one finding per violating operation, not per supporting evidence statement. When the proof is inconclusive, nothing is reported.

Exceptions (no report)

• Do not report unresolved or shadowed builtin names, unknown values, or incomplete receiver/type provenance. Unknown calls, aliases escaping, and intervening writes invalidate local proof. Similar code outside the stated detection contract is not a finding.
• Both standard suppression forms suppress this native ID.

Fix

None. Choosing a repair requires intent or additional runtime information.

PHP versions

Available throughout supported PHP 5.3–8.5 where the referenced builtin/extension is available. Respect syntax/version-specific receiver contracts; unavailable APIs are not this rule’s concern.

Configure

In custos.json:

{
  "rules": {
    "ProcessClosedBeforeOwnedPipes": {
      "enabled": false
    }
  }
}

Suppress

Before the statement or declaration (or the first statement of the file):

// @custos-ignore ProcessClosedBeforeOwnedPipes