[Xenomai-help] problem with reading from rt_pipe with a normal linux process

[Marco Jackel <ich@domain.hid>]

Hi,
i do the following:

- create a pipe:

rt_pipe_create (&data_pipe, "data_pipe", PIPE_MINOR, PIPE_SIZE);

- write data to the pipe:

rt_pipe_write(&data_pipe, &pipe_buf, pipe_buf_sz, P_NORMAL);

- open the pipe from a normal linux process:

pipe_fd = open(DATA_PIPE, O_RDONLY);

- read the data from the pipe:

ret = read(pipe_fd, &pipe_buf, sizeof(pipe_buf));


Opening works, but the reading doesn't work. I get the error code "-1",
Operation not permitted.

Permission for the device file is ok:

voyage:~# ls -l /dev/rtp0
crw-rw-rw-  1 root root 150, 0 Jun 21  2006 /dev/rtp0


What am I doing wrong?

Thanks
Marco


Linux voyage 2.6.16.1-03-xenomai-2.1.2 #1 PREEMPT Tue Jul 11 10:17:15
GMT 2006 i586 GNU/Linux

Gnu C                  17:
util-linux             2.12p
mount                  2.12p
module-init-tools      3.2-pre1
e2fsprogs              1.37
pcmcia-cs              3.2.5
PPP                    2.4.3
Linux C Library        2.3.2
Dynamic linker (ldd)   2.3.2
Procps                 3.2.1
Net-tools              1.60
Kbd                    69:
Sh-utils               5.2.1
Modules Loaded         xeno_16550A xeno_rtdm uhci_hcd ohci_hcd usbcore
dm_mod