ack/plat/msdos/libsys/sys_getmode.c

28 lines
509 B
C

/* $Source$
* $State$
* $Revision$
*/
#include <fcntl.h>
#include "libsys.h"
/*
* Say whether a particular fd is currently open in text or binary mode.
* Assume that the fd is valid. Return O_TEXT or O_BINARY.
*/
int _sys_getmode(int fd)
{
int reqbegfd = fd & ~_FDVECMASK;
struct _fdmodes *p = &_sys_fdmodes;
_fdvec_t mask;
while (p->begfd != reqbegfd)
{
p = p->next;
if (!p)
return O_TEXT;
}
mask = (_fdvec_t)1 << (fd & _FDVECMASK);
return (p->modevec & mask) ? O_BINARY : O_TEXT;
}