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REQ-F-072: LF Line Ending Enforcement

Tier: Framework-Automatic | Priority: P1

Source: Silent assumption — agents pipe output to Unix text tools (grep, awk, cut, wc) and assume LF line endings; CRLF produces "value\r" instead of "value" in string comparisons and field extractions

Addresses: Severity: High / Token Spend: Medium / Time: Low / Context: Low

Description

The framework MUST normalize all stdout and stderr output to LF (\n) line endings regardless of the host platform. On Windows, the framework MUST explicitly open stdout and stderr in binary mode and write \n — not the platform default \r\n. JSON output, text output, error messages, and help text MUST all use LF-only line endings.

CRLF in output is invisible in terminal emulators but breaks every downstream Unix text tool an agent may pipe to. grep "value" will not match "value\r". cut -f1 will include the \r in the last field. wc -l counts correctly but extracted values are corrupted.

Acceptance Criteria

  • tool list | cat -A | grep '\^M' returns no matches on any platform
  • JSON output written to a file contains no \r bytes
  • Help text (--help) contains no \r bytes
  • Error messages on stderr contain no \r bytes
  • Verified on: macOS, Linux, Windows (WSL and native)

Schema

No dedicated schema type — this requirement governs output encoding

Wire Format

All output streams use \n as the line terminator. JSON output is no exception — even though JSON spec allows \r\n, the framework emits \n-only.

Example

Without this requirement (broken on Windows):

$ tool list | grep "active"
"active\r"   ← grep matches but extracted value includes \r
$ tool list | awk '{print $2}'
"prod\r"     ← field extraction includes \r

With this requirement (correct on all platforms):

$ tool list | grep "active"
"active"
$ tool list | awk '{print $2}'
"prod"
Requirement Tier Relationship
REQ-F-005 F Extends: locale-invariant output also requires platform-invariant line endings
REQ-F-006 F Extends: stream enforcement applies to line ending consistency
REQ-F-016 F Composes: UTF-8 sanitization and LF enforcement both applied before output