source: buchla-68k/libcio/fseek.c@ 6262b5c

/*
   =============================================================================
        fseek.c -- perform a seek on a stream file
        Version 4 -- 1987-10-28 -- D.N. Lynx Crowe
   =============================================================================
*/

#include "all.h"

extern  int32_t lseek(int16_t fd, int32_t pos, int16_t how);

extern  int16_t flush_(FILE *ptr, int16_t data);

/*
   =============================================================================
        fseek(fp, pos, mode) -- position file 'fp' at 'pos' in mode 'mode'.
   =============================================================================
*/

int16_t fseek(FILE *fp, int32_t pos, int16_t mode)
{
        register int16_t i, lr;
        int32_t curpos;

        if (fp->_flags & _DIRTY) {

                if (flush_(fp, -1))
                        return(EOF);

        } else {

                if (mode EQ 1 AND fp->_bp)
                        pos -= (int32_t)fp->_bend - (int32_t)fp->_bp;
        }

        fp->_bp = fp->_bend = NULL;
        fp->_flags &= ~_EOF;

        lr = lseek(fp->_unit, pos, mode);

        if (((struct fcb *)chantab[fp->_unit].c_arg)->modefl & FC_EOF)
                fp->_flags |= _EOF;

        if (lr < 0)
                return(EOF);

        return(0);
}