88 lines
		
	
	
	
		
			1.5 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			88 lines
		
	
	
	
		
			1.5 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
/*
 | 
						|
 * freopen.c - open a file and associate a stream with it
 | 
						|
 */
 | 
						|
/* $Header$ */
 | 
						|
 | 
						|
#include	<stdio.h>
 | 
						|
#include	<stdlib.h>
 | 
						|
#include	<sys/file.h>
 | 
						|
#include	"loc_incl.h"
 | 
						|
 | 
						|
#define  PMODE    0666
 | 
						|
int open(const char *path, int flags, int mode);
 | 
						|
int close(int d);
 | 
						|
 | 
						|
FILE *
 | 
						|
freopen(const char *name, const char *mode, FILE *stream)
 | 
						|
{
 | 
						|
	register int i;
 | 
						|
	int rwmode = 0, rwflags = 0;
 | 
						|
	int fd, flags = stream->_flags & ~(_IOWRITE|_IOREAD|_IOERR|_IOEOF);
 | 
						|
 | 
						|
	(void) fflush(stream);				/* ignore errors */
 | 
						|
	(void) close(fileno(stream));
 | 
						|
 | 
						|
	switch(*mode++) {
 | 
						|
 | 
						|
	case 'r':
 | 
						|
		flags |= _IOREAD;	
 | 
						|
		rwmode = O_RDONLY;
 | 
						|
		break;
 | 
						|
 | 
						|
	case 'w':
 | 
						|
		flags |= _IOWRITE;
 | 
						|
		rwmode = O_WRONLY;
 | 
						|
		rwflags = O_CREAT | O_TRUNC;
 | 
						|
		break;
 | 
						|
 | 
						|
	case 'a': 
 | 
						|
		flags |= _IOWRITE;
 | 
						|
		rwmode = O_WRONLY;
 | 
						|
		rwflags |= O_APPEND | O_CREAT;
 | 
						|
		break;         
 | 
						|
 | 
						|
	default:
 | 
						|
		return (FILE *)NULL;
 | 
						|
	}
 | 
						|
 | 
						|
	while (*mode) {
 | 
						|
		switch(*mode++) {
 | 
						|
 | 
						|
		case 'b':
 | 
						|
			break;
 | 
						|
 | 
						|
		case '+':
 | 
						|
			rwmode = O_RDWR;
 | 
						|
			flags |= _IOREAD | _IOWRITE;
 | 
						|
			break;
 | 
						|
 | 
						|
		default:
 | 
						|
			return (FILE *)NULL;
 | 
						|
 | 
						|
		}
 | 
						|
	}
 | 
						|
 | 
						|
	fd = open(name, rwmode | rwflags, PMODE);
 | 
						|
 | 
						|
	if (fd < 0) {
 | 
						|
		for( i = 0; i < FOPEN_MAX; i++) {
 | 
						|
			if (stream == _iotable[i]) {
 | 
						|
				_iotable[i] = 0;
 | 
						|
				break;
 | 
						|
			}
 | 
						|
		}
 | 
						|
		if (stream != stdin && stream != stdout && stream != stderr)
 | 
						|
			free((void *)stream);
 | 
						|
		return (FILE *)NULL;
 | 
						|
	}
 | 
						|
 | 
						|
	stream->_count = 0;
 | 
						|
	if (stream->_buf && !(flags & _IONBF) && (flags & _IOWRITE)) 
 | 
						|
		if (flags & _IOLBF)
 | 
						|
			stream->_count  = 0;
 | 
						|
		else	stream->_count = stream->_bufsiz;
 | 
						|
 | 
						|
	stream->_fd = fd;
 | 
						|
	stream->_flags = flags;
 | 
						|
	return stream;
 | 
						|
}
 |