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Cream of the Crop 1
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Cream of the Crop 1.iso
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PROGRAM
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DJLSR106.ARJ
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FSEEK.C
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C/C++ Source or Header
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1992-03-02
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86 lines
/* This is file FSEEK.C */
/* This file may have been modified by DJ Delorie (Jan 1991). If so,
** these modifications are Coyright (C) 1991 DJ Delorie, 24 Kirsten Ave,
** Rochester NH, 03867-2954, USA.
*/
/* This file was modified 1991-10-20 by R. Davidson in order to correct
** for ascii text files.
*/
#if defined(LIBC_SCCS) && !defined(lint)
static char sccsid[] = "@(#)fseek.c 5.3 (Berkeley) 3/9/86";
#endif LIBC_SCCS and not lint
/*
* Seek for standard library. Coordinates with buffering.
*/
#include <stdio.h>
long lseek();
fseek(iop, offset, ptrname)
register FILE *iop;
long offset;
{
register resync, c;
long p = -1; /* can't happen? */
long adjust = 0;
char *q, *qq;
iop->_flag &= ~_IOEOF;
if (iop->_flag&_IOREAD) {
if (ptrname<2 && iop->_base &&
!(iop->_flag&_IONBF)) {
c = iop->_cnt;
p = offset;
if (ptrname==0) {
long curpos = lseek(fileno(iop), 0L, 1);
if (curpos == -1)
return (-1);
p += c - curpos;
} else
offset -= c;
if(!(iop->_flag&_IORW) && c>0&&p<=c
&& p>=iop->_base-iop->_ptr){
if (iop->_flag&_IOTEXT){
q = &iop->_ptr[iop->_cnt];
qq = iop->_ptr + (int)p;
while (--q >= qq)
if (*q == '\n'){
adjust++; qq++;
}
p += adjust;
}
iop->_ptr += (int)p;
iop->_cnt -= (int)p;
return(0);
}
resync = offset&01;
} else
resync = 0;
if (iop->_flag & _IORW) {
iop->_ptr = iop->_base;
iop->_flag &= ~_IOREAD;
resync = 0;
}
p = lseek(fileno(iop), offset-resync, ptrname);
iop->_cnt = 0;
if (resync && p != -1)
if (getc(iop) == EOF)
p = -1;
}
else if (iop->_flag & (_IOWRT|_IORW)) {
p = fflush(iop);
if (iop->_flag & _IORW) {
iop->_cnt = 0;
iop->_flag &= ~_IOWRT;
iop->_ptr = iop->_base;
}
return(lseek(fileno(iop), offset, ptrname) == -1 || p == EOF ?
-1 : 0);
}
return(p==-1?-1:0);
}