l4_ipc_receive -- wait for a message from a specified thread

#include <l4/sys/ipc.h>

static inline int
l4_ipc_receive(l4_threadid_t src , void *rcv_msg , l4_umword_t *rcv_dword0 , l4_umword_t *rcv_dword1 l4_timeout_t timeout , l4_msgdope_t *result );

2 Description

src

Thread id of the source.

*rcv_msg

Pointer to Receive Descriptor. It can contain the following values:

0

Only messages up to two 32-bit words and are accepted. The received message is returned in rcv_dword0 and rcv_dword1.

<mem>

If Bit 1 of *rcv_msg is 0 ipc includes receiving a message respectively waiting to receive a message. *rcv_msg must point to a valid message. Note that the first two 32-bit words of the received message are returned in rcv_dword0 and rcv_dword1.

<rmap>

If Bit 1 of *rcv_msg is 1 only send-fpage messages or up to two 32-bit words (in rcv_dword0 and rcv_dword1) are accepted. If a map message is received, the 30 most significant bits describe the receive fpage (instead of rcvfpage option in a memory message buffer). Thus fpages can also be received without a message buffer in memory.

*rcv_dword0

First of two 32-bit words of received message, undefined if no message was received.

*rcv_dword1

Second of two 32-bit words of received message, undefined if no message was received.

timeout

This 32-bit word specifies all 4 timouts, the quadruple (snd, rcv, snd pf, rcv pf). For a detailed description see the L4 Reference Manual.

result

The message dope describing the result of the Ipc.

0

No error occured. The optional send operation was successful, and if a receive operation was also specified, a message was also received correctly.

L4_IPC_ENOT_EXISTENT

Non-existing destination or source.

L4_IPC_RETIMEOUT

Timeout during receive operation.

L4_IPC_SETIMEOUT

Timeout during send operation.

L4_IPC_RECANCELED

Receive operation cancelled by another thread.

L4_IPC_SECANCELED

Send operation cancelled by another thread.

L4_IPC_REMAPFAILED

Map failed due to a shortage of page tables during receive operation.

L4_IPC_SEMAPFAILED

Map failed due to a shortage of page tables during send operation.

L4_IPC_RESNDPFTO

Send pagefault timeout.

L4_IPC_SERCVPFTO

Receive pagefault timeout.

L4_IPC_REABORTED

Receive operation aborted by another thread.

L4_IPC_SEABORTED

Send operation aborted by another thread.

L4_IPC_REMSGCUT

Received message cut. Potential reasons are:

(a)

The recipient's mword buffer is too small.

(b)

The recipient does not accept enough strings.

(c)

At least one of the recipient's string buffers is too small.