Path: utzoo!attcan!uunet!cs.utexas.edu!tut.cis.ohio-state.edu!unmvax!ogccse!blake!uw-beaver!tektronix!sequent!paulr
From: paulr@sequent.UUCP (Paul Reger)
Newsgroups: comp.unix.wizards
Subject: Re: how can I get filename from file descriptor?
Keywords: Name of file given the FILE * or fd.
Message-ID: <20644@sequent.UUCP>
Date: 24 Aug 89 19:03:25 GMT
References: <20613@adm.BRL.MIL> <1019@virtech.UUCP> <20482@sequent.UUCP> <19208@mimsy.UUCP>
Reply-To: paulr@crg3.UUCP (Paul Reger)
Organization: Sequent Computer Systems, Inc
Lines: 32

In article <19208@mimsy.UUCP> chris@mimsy.UUCP (Chris Torek) writes:
>In article <20482@sequent.UUCP> paulr@sequent.UUCP (Paul Reger) writes:
>>What I mean is this ...
>>Have the FILE structure have a name field in it:
>>    char *name;
>>then when the fopen() call is made, have it fill in the field ....
>
>This is all well and good, but you will have to define what happens
>when you ask for the name of stdin, stdout, stderr,

This being the case maybe to solve the real problem is to provide one
kernel-level mapping:

char *
Name(f)
FILE *f;  /* Or fd... */

Which would yield the name of any file (be it a pipe, stdin, stdout,
stderr, file, a psudo tty or any gawd-awful thingy that exists...
Each would have to be special cased except for the open files which
are actual disk files (posses actual file names...).

>or a file opened
>with fdopen.  (Also, but rather incidentally, I am not terribly thrilled 
>with the idea of fopen having to call getwd.)

Maybe have two sets of kernel open()'s one with 'name saving' one
without.... 

             paulr       (Paul Reger)
     Sequent Computer Systems  Beaverton, OR.
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