Signal Handling

The EVM API does not use signals in its normal processing and does not interfere with an application program's use of signals. However, because the system's default action is to silently terminate a process that attempts to write to a local connection if no process exists to read the data, a client process can exit without trace if the EVM daemon terminates before or during activity on the connection.

To prevent this, the EvmConnCreate() function checks whether the caller has already established a handler for SIGPIPE; if not, the function installs a default handler. The handler takes no action if the signal occurs, but its presence prevents the client from terminating. A program can override the EVM handler by setting its own handler either before or after the call to EvmConnCreate(). If it is important that the program takes the default action, set the action to SIG_DFL after calling EvmConnCreate().

For more information about signals, see signal(2).