SendZc doesn't work, when Send works

[Eugene-Usachev]

For a long time, I have been trying to find a bug in the code that works on my local machine, which does not support SendZc, and uses Send. However, it does not work on the machine that supports and uses SendZc.

I am unable to provide a theory as to why this is happening. In both cases, the buffer reference is valid until the result is returned. However, SendZc is causing an error with the message "Invalid memory reference (SIGSEGV)". Do SendZc and SendMsgZc have any additional restrictions?