Re^2: Detect whether a writeable filehandle has closed?

[jdporter]

Maybe an END block in the child could signal that the filehandle is gone

The child is not perl, it's a compiled C program.

[talexb]

OK, so perhaps using the _atexit call (or whatever the equivalent is in your RTL) in the C code. The general idea is for the code to catch that the child has exitted and signal the caller.