ResMgr and MsgSend from within the same process

QNX Newsgroups (Archives) comp.os.qnx
1

I have a process that uses IPc. I have created a resmgr in a thread
that waits for messages to arrive. If I send a message from another
process, everything works fine. If I try to open(), then MsgSend() from
within the same process (different thread), the open fails with file not
found. Is it illegal to send a message to myself when using resmgr?

Thanks.


Gregor Brandt

2

Gregor Brandt <gbrandt@oerlikon.ca> wrote:

I have a process that uses IPc. I have created a resmgr in a thread
that waits for messages to arrive. If I send a message from another
process, everything works fine. If I try to open(), then MsgSend() from
within the same process (different thread), the open fails with file not
found. Is it illegal to send a message to myself when using resmgr?

Check lib reference, resmgr_attach(), flag _RESMGR_FLAG_SELF

-xtang

3

Gregor Brandt <gbrandt@oerlikon.ca> wrote:

I have a process that uses IPc. I have created a resmgr in a thread
that waits for messages to arrive. If I send a message from another
process, everything works fine. If I try to open(), then MsgSend() from
within the same process (different thread), the open fails with file not
found. Is it illegal to send a message to myself when using resmgr?

No, not illegal. To do an open() on yourself requires a special flag
as noted in the other response.

Do you really need/want open() behaviour and everything with it between
your threads in the resmgr, though? (That is, do you intend to use this
connection for reads/writes or similar fd behaviour.) You may also want
to take a look at message_connect() for getting a connection to yourself
and message_attach() for handling non IO messages.

-David

QNX Training Services
dagibbs@qnx.com