Signal Handling

JRuby supports the same Signal API that CRuby does, but there will be differences due to how various JVMs use those signals internally. Signals that are captured by the JVM will generally not be available for JRuby programs.

In some cases, as with Hotspot (OpenJDK/OracleJDK) there may be ways to reduce JVM signal usage (e.g. the -Xrs flag for Hotspot).

• Hotspot is known to use SEGV in its garbage collector.
• Hotspot may use USR1 and USR2 on some platforms.
• Hotspot connects INT to a JVM-wide hard shutdown. If you wish to capture this signal, you must trap it yourself; unlike CRuby, JRuby will not automatically bind it to an Interrupt-raising handler.
• Platform-specific signals may not be mapped into JRuby, due to the fact that we have no per-platform compile phase.