various doubts ......

various doubts ......

[joy]

Hello,
I  have a few , though unconnected doubts.

1) can a named pipe be locked using normal lockf()  or do I have to 
perform some voodoo?

2) I need to transfer data (protocol not an issue, just raw data) from a 
usb peripheral(not HDD)
    to the host comp. can I do this without writing a usb driver myself, 
i.e , using some generic or user-space driver (like ppdev)
    the peripheral is a texas instruments tusb246b hub.

Thanx in advance,
Joy.M.Monteiro

Re: various doubts ......

[Luiz Fernando N. Capitulino]

 Hi Joy,

Em Mon, 09 Aug 2004 22:50:25 +0530
joy <gracecott@sancharnet.in> screveu:

| Hello,
| I  have a few , though unconnected doubts.
| 
| 1) can a named pipe be locked using normal lockf()  or do I have to 
| perform some voodoo?

 I think is possible, but take a look at fcntl(2).

| 2) I need to transfer data (protocol not an issue, just raw data) from a 
| usb peripheral(not HDD)
|     to the host comp. can I do this without writing a usb driver myself, 
| i.e , using some generic or user-space driver (like ppdev)
|     the peripheral is a texas instruments tusb246b hub.

 If I've understand what you mean: maybe. The question is: there is any driver
for that hub in the kernel ?

 As far as I read, in ppdev you do have two things. First, there is the
/dev/lp0, which is the _printer_ driver; second, there is the /dev/parport0,
the _parallel port_ driver.

 You can write a user-space driver for you printer, because the kernel
already give you a way (driver) to acesses the parallel port, through
/dev/parport0.

 There is this kind of thing for your USB device ?

 hope this helps,

PS: Don't know nothing about printers, so I may be wrong.

-- 
Luiz Fernando

Re: various doubts ......

[joy]

joy wrote:

> Hello,
> I  have a few , though unconnected doubts.
>
> 1) can a named pipe be locked using normal lockf()  or do I have to 
> perform some voodoo?
>
Yes it can! I tried it out with two processes trying to write to the 
pipe at the same time.One obtains the  lock
and sleep()s for 10 seconds during which the other process is blocked.

> 2) I need to transfer data (protocol not an issue, just raw data) from 
> a usb peripheral(not HDD)
>    to the host comp. can I do this without writing a usb driver 
> myself, i.e , using some generic or user-space driver (like ppdev)
>    the peripheral is a texas instruments tusb246b hub.
>
> Thanx in advance,
> Joy.M.Monteiro
> -
> To unsubscribe from this list: send the line "unsubscribe 
> linux-c-programming" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>