Hello,
now i’m reading microkernel architecture and have some questions. book
recomends to write applications divided into processes. so i can’t
understand the meaning of process. is it the same as threads in windows?
or maybe processes in qnx is diferent executables running at the same
time? maybe someone can give clear picture of processes meaning?
thanks.
Darius
In article <cc9mlg$dk$1@inn.qnx.com>, alpha_byte@safe-mail.net says…
Hello,
now i’m reading microkernel architecture and have some questions. book
What is exact the title of the book? Is it about QNX6 or QNX4? Both QNX4
and QNX6 are microkernel RTOS, but QNX4 has no thread support (well,
rumour says there is quite limited support).
recomends to write applications divided into processes. so i can’t
understand the meaning of process. is it the same as threads in windows?
Process is one or few threads running in separated memory space. Process
could be spawned (by the shell, for example) or forked by parent
process. Usually process is about to solve some task within a system.
Process is a container for threads. Threads share common memory within a
process. Thread is about to solve some task within a process. For
communication between the threads of particular process you can use
global variables. For communication between processes you need IPC
(message passing is a QNX way) or shared memory.
I guess the book says, if your application is data acquisition system
you may want to divide the application into the driver (resource
manager), the process communicating with driver for writing data to disk
and process for visualisation some data to user. Every of these
processes can consist of few threads.
Cheers,
Eduard.
or maybe processes in qnx is diferent executables running at the same
time? maybe someone can give clear picture of processes meaning?
thanks.Darius
hello,
What is exact the title of the book? Is it about QNX6 or QNX4? Both QNX4
and QNX6 are microkernel RTOS, but QNX4 has no thread support (well,
rumour says there is quite limited support).
think this was QNX 4 
is there any chance to get online books from qnx
website to use them offline (in pdf or other format)?
Darius
alpha <alpha_byte@safe-mail.net> wrote:
hello,
What is exact the title of the book? Is it about QNX6 or QNX4? Both QNX4
and QNX6 are microkernel RTOS, but QNX4 has no thread support (well,
rumour says there is quite limited support).think this was QNX 4 >
website to use them offline (in pdf or other format)?
Not if you’re using QNX 4. Our production department might still have some
printed books; please ask your sales representative.
Not if you’re using QNX 4. Our production department might still have
some
printed books; please ask your sales representative.
no no I’m using 6.2.1 version but i have printed books for QNX4. I need some
documentation available offline for QNX6. can you help?
Darius
alpha <alpha_byte@safe-mail.net> wrote:
Not if you’re using QNX 4. Our production department might still have
some
printed books; please ask your sales representative.no no I’m using 6.2.1 version but i have printed books for QNX4. I need some
documentation available offline for QNX6. can you help?
Try:
http://www.parse.com/products/books/book_v3.html
and
http://www.parse.com/products/books/book_v2.html
Both of these books are available from QNX as well as from us and our
distributors, depending on where you are located…
Cheers,
-RK
–
[If replying via email, you’ll need to click on the URL that’s emailed to you
afterwards to forward the email to me – spam filters and all that]
Robert Krten, PDP minicomputer collector http://www.parse.com/~pdp8/
Darius <alpha_byte@safe-mail.net> wrote:
Hello,
now i’m reading microkernel architecture and have some questions. book
recomends to write applications divided into processes. so i can’t
understand the meaning of process. is it the same as threads in windows?
or maybe processes in qnx is diferent executables running at the same
time? maybe someone can give clear picture of processes meaning?
thanks.
A process is a complete program loaded into memory as an independent
entity. It is seperately startable and terminatable and owns a set
of resources, primarily meaning code and data, but also including
fds, timers, and others. It must include at least one thread (stream
of execution), and may have multiple threads.
Please follow-up to newsgroup, rather than personal email.
David Gibbs
QNX Training Services
dagibbs@qnx.com