BrokenPipeError: Broken Pipe

Why This Happens

When you pipe output (python script.py | head -5), head closes the pipe after reading enough lines. Further writes to stdout raise BrokenPipeError. This is normal behavior.

The Problem

# python script.py | head -5
for i in range(1000000):
    print(i)  # BrokenPipeError when head closes

The Fix

import sys
import signal

# Ignore SIGPIPE:
signal.signal(signal.SIGPIPE, signal.SIG_DFL)

# Or handle the error:
try:
    for i in range(1000000):
        print(i)
except BrokenPipeError:
    sys.stderr.close()
    sys.exit(0)

Step-by-Step Fix

1. 1

   Handle BrokenPipeError

   Wrap output in try/except BrokenPipeError.

2. 2

   Reset SIGPIPE

   Use signal.signal(signal.SIGPIPE, signal.SIG_DFL).

3. 3

   Flush output

   Use sys.stdout.flush() after critical writes.