fix(core): wrap print calls with try-except OSError#1358
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Prevents agent crashes in headless environments (Docker, systemd) where stdout might be unavailable. Fixes NousResearch#845.
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The approach is right but there's a bug: the Fix: keep those two lines before the try block. The try-except should only wrap the print() calls, not the variable assignments. |
teknium1
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Mar 17, 2026
In headless environments (systemd, Docker, nohup) stdout can become unavailable mid-session. Raw print() raises OSError which crashes cron jobs — agent finishes work but delivery never happens because the error handler's own print() also raises OSError. Fix: - Add _safe_print() static method that wraps print() with try/except OSError — silently drops output when stdout is broken - Make _vprint() use _safe_print() — protects all calls through the verbose print path - Convert raw print() calls in run_conversation() hot path to use _safe_print(): starting conversation, interrupt, budget exhausted, preflight compression, context cache, conversation completed - Error handler print (the cascading crash point) gets explicit try/except with logger.error() fallback so diagnostics aren't lost Fixes #845 Closes #1358 (superseded — PR was 323 commits stale with a bug)
angelburgosrosado
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Apr 27, 2026
In headless environments (systemd, Docker, nohup) stdout can become unavailable mid-session. Raw print() raises OSError which crashes cron jobs — agent finishes work but delivery never happens because the error handler's own print() also raises OSError. Fix: - Add _safe_print() static method that wraps print() with try/except OSError — silently drops output when stdout is broken - Make _vprint() use _safe_print() — protects all calls through the verbose print path - Convert raw print() calls in run_conversation() hot path to use _safe_print(): starting conversation, interrupt, budget exhausted, preflight compression, context cache, conversation completed - Error handler print (the cascading crash point) gets explicit try/except with logger.error() fallback so diagnostics aren't lost Fixes NousResearch#845 Closes NousResearch#1358 (superseded — PR was 323 commits stale with a bug)
02356abc
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May 14, 2026
In headless environments (systemd, Docker, nohup) stdout can become unavailable mid-session. Raw print() raises OSError which crashes cron jobs — agent finishes work but delivery never happens because the error handler's own print() also raises OSError. Fix: - Add _safe_print() static method that wraps print() with try/except OSError — silently drops output when stdout is broken - Make _vprint() use _safe_print() — protects all calls through the verbose print path - Convert raw print() calls in run_conversation() hot path to use _safe_print(): starting conversation, interrupt, budget exhausted, preflight compression, context cache, conversation completed - Error handler print (the cascading crash point) gets explicit try/except with logger.error() fallback so diagnostics aren't lost Fixes NousResearch#845 Closes NousResearch#1358 (superseded — PR was 323 commits stale with a bug)
olympus-terminal
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May 16, 2026
In headless environments (systemd, Docker, nohup) stdout can become unavailable mid-session. Raw print() raises OSError which crashes cron jobs — agent finishes work but delivery never happens because the error handler's own print() also raises OSError. Fix: - Add _safe_print() static method that wraps print() with try/except OSError — silently drops output when stdout is broken - Make _vprint() use _safe_print() — protects all calls through the verbose print path - Convert raw print() calls in run_conversation() hot path to use _safe_print(): starting conversation, interrupt, budget exhausted, preflight compression, context cache, conversation completed - Error handler print (the cascading crash point) gets explicit try/except with logger.error() fallback so diagnostics aren't lost Fixes NousResearch#845 Closes NousResearch#1358 (superseded — PR was 323 commits stale with a bug)
gweeteve
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Jun 2, 2026
In headless environments (systemd, Docker, nohup) stdout can become unavailable mid-session. Raw print() raises OSError which crashes cron jobs — agent finishes work but delivery never happens because the error handler's own print() also raises OSError. Fix: - Add _safe_print() static method that wraps print() with try/except OSError — silently drops output when stdout is broken - Make _vprint() use _safe_print() — protects all calls through the verbose print path - Convert raw print() calls in run_conversation() hot path to use _safe_print(): starting conversation, interrupt, budget exhausted, preflight compression, context cache, conversation completed - Error handler print (the cascading crash point) gets explicit try/except with logger.error() fallback so diagnostics aren't lost Fixes NousResearch#845 Closes NousResearch#1358 (superseded — PR was 323 commits stale with a bug)
Egavasyug
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Jun 10, 2026
In headless environments (systemd, Docker, nohup) stdout can become unavailable mid-session. Raw print() raises OSError which crashes cron jobs — agent finishes work but delivery never happens because the error handler's own print() also raises OSError. Fix: - Add _safe_print() static method that wraps print() with try/except OSError — silently drops output when stdout is broken - Make _vprint() use _safe_print() — protects all calls through the verbose print path - Convert raw print() calls in run_conversation() hot path to use _safe_print(): starting conversation, interrupt, budget exhausted, preflight compression, context cache, conversation completed - Error handler print (the cascading crash point) gets explicit try/except with logger.error() fallback so diagnostics aren't lost Fixes NousResearch#845 Closes NousResearch#1358 (superseded — PR was 323 commits stale with a bug)
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What does this PR do?
This PR wraps multiple
print()calls within therun_conversationfunction inrun_agent.pywithtry...except OSErrorblocks.It prevents the agent from crashing with a
Broken PipeorInput/output errorwhen running in headless environments (like Docker containers, systemd services, or remote CI/CD) where a terminal (stdout) might be unavailable or disconnected.Why is this necessary?
Currently, the agent's core loop can fail entirely if it attempts to output progress messages to a non-existent terminal. This change ensures that the agent's logic remains robust and continues to execute even if visual output fails.
Related Issue
Fixes #845