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Full Discussion: File Descriptor Table
Top Forums UNIX for Advanced & Expert Users File Descriptor Table Post 302148526 by fsahog on Sunday 2nd of December 2007 09:04:46 PM
Old 12-02-2007
Not sure we're answering your question..

Quote:
Originally Posted by Ashaman0
Im working on writing a small operating system. I am currently working on implementing dup, dup2, pipe, and close and I need to implement some type of file descriptor table in my PCB.

I was wondering if there is anyone who is familiar with linux/unix implementation of these tables who could explain to me a little about how they are implemented. I know basically how it works, what I am really having a little trouble with now is how file descriptors are mapped to input/output streams. Are their pointers to the pipe / device, or is there some other way its done? Thanks.

-shane
Streams must necessarily have a file descriptor as one of their attributes. Streams are a higher level processing construct than the driver level open/close/read/write/ioctl entry points. Generally they at least manage a buffering logic that works "above" what's actually going on in the kernel's queueing mechanisms.

You can email me direct email address removed if you want a more rapid dialogue.

S.

Last edited by vino; 12-03-2007 at 12:14 AM.. Reason: email address removed
 

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