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--- probing-mpi [June 11, 2026 at 09:10] – created - external edit 127.0.0.1
+++ probing-mpi [June 11, 2026 at 09:15] (current) – Ivan Janevski
@@ Line 1: / Line 1: @@
 # Probing for messages (MPI)
-A standard `recv()` on a socket requires a pre-allocated buffer. If the incoming message is larger than the buffer, data gets truncated or the call fails. The POSIX escape hatch is `MSG_PEEK`: pass it as a flag and `recv()` fills your buffer but leaves the data in the socket queue, letting you inspect the size before committing to a real receive. `ioctl(fd, FIONREAD, &n)` goes further and tells you exactly how many bytes are waiting. MPI's `MPI_Probe` does the same thing: it matches an incoming message and fills an `MPI_Status` struct with metadata — including the element count — without consuming the message from the queue.
+A standard `recv()` on a socket requires a pre-allocated buffer. If the incoming message is larger than the buffer, data gets truncated or the call fails. The POSIX escape hatch is `MSG_PEEK`: pass it as a flag and `recv()` fills your buffer but leaves the data in the socket queue, letting you inspect the size before committing to a real receive. `ioctl(fd, FIONREAD, &n)` goes further and tells you exactly how many bytes are waiting.
+MPI's `MPI_Probe` does the same thing: it matches an incoming message and fills an `MPI_Status` struct with metadata — including the element count — without consuming the message from the queue.
 ```c