sysinq.c

来自「开放源码的编译器open watcom 1.6.0版的源代码」· C语言 代码 · 共 110 行

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*
*                            Open Watcom Project
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*  ========================================================================
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*    This file contains Original Code and/or Modifications of Original
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//
// SYSINQ       : system dependent INQUIRE support
//

#include "ftnstd.h"
#include "ftnio.h"

extern  bool                    IsDevice(ftnfile *);


int     InqSeq( ftnfile *fcb ) {
//==============================

// Return ACCM_SEQUENTIAL if sequential is in the allowed set of access
//                        modes for the given file,
//        ACCM_DIRECT     if not,
//        ACCM_DEFAULT    if we can't decide.

    if( fcb->accmode == ACCM_DIRECT ) {
        if( fcb->formatted == FORMATTED_IO ) {
            return( ACCM_SEQUENTIAL );
        }
        if( fcb->recfm == RECFM_VARIABLE ) {
            return( ACCM_SEQUENTIAL );
        }
        return( ACCM_DIRECT );
    }
    return( ACCM_SEQUENTIAL );
}


int     InqDir( ftnfile *fcb ) {
//==============================

// Return ACCM_DIRECT     if direct is in the allowed set of access modes
//                        for the given file,
//        ACCM_SEQUENTIAL if not,
//        ACCM_DEFAULT    if we can't decide.
//

    if( IsDevice( fcb ) ) {
        return( ACCM_SEQUENTIAL );
    }
    if( fcb->accmode == ACCM_DIRECT ) {
        return( ACCM_DIRECT );
    }
    if( fcb->recfm == RECFM_FIXED ) {
        return( ACCM_DIRECT );
    }
    return( ACCM_SEQUENTIAL );
}


int     InqFmtd( ftnfile *fcb ) {
//===============================

// Return FORMATTED_IO   if formatted is "in the allowed set of format
//                       modes for the given file",
//        UNFORMATTED_IO if not,
//        FORMATTED_DFLT if we can't decide.
//

    return( fcb->formatted );
}


int     InqUnFmtd( ftnfile *fcb ) {
//=================================

// Return UNFORMATTED_IO if unformatted is "in the allowed set of format
//                       modes for the given file",
//        FORMATTED_IO   if not,
//        FORMATTED_DFLT if we can't decide.
//

    return( fcb->formatted );
}