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asyncmsg_connect_attach()

Establish a connection between a process and a channel

Synopsis:

#include <sys/neutrino.h>
#include <sys/asyncmsg.h>

int asyncmsg_connect_attach;
            (uint32_t nd, pid_t pid, int chid,
            unsigned index, unsigned flags, 
            const struct _asyncmsg_connection_attr *attr);

Arguments:

nd

The node descriptor.

pid

The process ID of the owner of the channel.

chid

The channel ID, returned by asyncmsg_channel_create(), of the channel to connect to the process.

index

The value of the connection ID.

flags

Flags that specify the type and attributes of the connection:

_NTO_COF_NOSHARE: User wants to use its own buffer; otherwise the user gets the buffer from the asyncmsg_malloc() call, fills it in and sends it by calling the asyncmsg_put() function.
_NTO_COF_NONBLOCK: Don't block waiting if all the send headers are in use.

attr

The connection attributes. If call_back is not NULL, this function will be called when an error occurs during send (after asyncmsg_put() returns) with an error number in err and the faulted buffer in buff. If the user uses its own buffer, this function will also be called when a buffer is empty, with err being EOK.

Library:

libasyncmsg

Use the -l asyncmsg option to qcc to link against this library.

Description:

The asyncmsg_connect_attach() function establishes a connection between the calling process and a channel identified by the arguments nd, pid and chid. The system returns the first available connection ID starting at the value specified by the index argument.

Returns:

A connection ID on success; or -1 if an error occurred (errno is set).

Errors:

EAGAIN: All kernel channel objects are in use.
ESRCH: The node indicated by nd, the process indicated by pid or the channel indicated by chid does not exist.

Classification:

QNX Neutrino

Safety:
Cancellation point	No
Interrupt handler	No
Signal handler	No
Thread	Yes