SimSerial: line-buffer stdout so log lines flush promptly - #38
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SimSerial routes Serial output to stdout via putchar(). When stdout is not a TTY (a pipe, a file, or under a service manager), C stdio defaults to full buffering, so log lines don't appear until a ~4 KB buffer fills — forcing callers to wrap the process in `stdbuf -oL`. Set stdout to line-buffered once, at the first SimSerial construction (the global `Serial` is built at static-init, before any output), so each Serial.print line is flushed on its newline and reaches the terminal / journald promptly. Guarded to run once: setvbuf() is undefined after I/O has begun, and extra SimSerial instances may be constructed later (e.g. tests). Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01KzBaSxeXYbJBJ7EYyfR3Lb
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SimSerial routes Serial output to stdout via putchar(). When stdout is not a TTY (a pipe, a file, or under a service manager), C stdio defaults to full buffering, so log lines don't appear until a ~4 KB buffer fills — forcing callers to wrap the process in
stdbuf -oL.