diff --git a/README.md b/README.md
index f437635..efc1055 100644
--- a/README.md
+++ b/README.md
@@ -131,7 +131,10 @@ Non-TPDU messages (ATR, PPS, card state changes, Fi/Di) print identically in all
 
 ## Background / Daemon
 
-SIGHUP is ignored by default — terminal closure won't kill the sniffer.
+SIGHUP is automatically ignored when stdin is not a terminal (i.e. run in
+background or via a pipe). Foreground terminal sessions still respond to
+SIGHUP normally.
+
 To run persistently in the background with output to files:
 
 ```sh
diff --git a/simtrace2_pysniff/__main__.py b/simtrace2_pysniff/__main__.py
index 4b49d82..671f7cd 100644
--- a/simtrace2_pysniff/__main__.py
+++ b/simtrace2_pysniff/__main__.py
@@ -131,7 +131,8 @@ def main():
             file_dumper.close()
         sys.exit(0)
 
-    signal.signal(signal.SIGHUP, signal.SIG_IGN)
+    if not sys.stdin.isatty():
+        signal.signal(signal.SIGHUP, signal.SIG_IGN)
     signal.signal(signal.SIGINT, on_signal)
     signal.signal(signal.SIGTERM, on_signal)