pSOSystem System Calls - Read

q_vreceive pSOS+ System Calls
q_vreceive Requests a message from a variable-length message queue.
#include
unsigned long q_vreceive(
unsigned long qid, /* queue identifier */
unsigned long flags, /* queue attributes */
unsigned long timeout, /* timeout in clock ticks */
void *msg_buf, /* message buffer */
unsigned long buf_len, /* length of buffer */
unsigned long *msg_len /* length of message */
)
Description
Arguments
This system call enables a task or an ISR to obtain a message from a variable length
message queue. Otherwise, it is identical to q_receive().
qid Specifies the queue ID of the target queue.
flags Specifies whether q_vreceive() will block waiting for a
message. flags should have one of the following values
(defined in ):
Q_NOWAIT /
Q_WAIT
Don't wait / wait for message..
timeout Specifies the timeout interval, in units of clock ticks. If timeout
is zero and Q_WAIT is selected, then q_vreceive() will wait
forever. timeout will be ignored if Q_NOWAIT is selected.
msg_buf Points to the buffer that receives the message.
buf_len Specifies the length of the buffer msg_buf points to. If buf_len
is less than the queue's maximum message length,
ERR_BUFSIZ is returned to the caller.
msg_len Points to the variable where q_receive() stores the actual
length of the received message.
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