write.c

基于Xilinx-XUPV2P开发平台的嵌入式系统实验例程：实验4编写基本的应用程序

////////////////////////////////////////////////////////////////////////////////
// Copyright (c) 2004 Xilinx, Inc.  All rights reserved. 
// 
// Xilinx, Inc. 
// XILINX IS PROVIDING THIS DESIGN, CODE, OR INFORMATION "AS IS" AS A 
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// $Id : $
////////////////////////////////////////////////////////////////////////////////

/* write.c -- write bytes to an output device.
 */

extern int  outbyte(char);

/*
 * write -- write bytes to the serial port. Ignore fd, since
 *          stdout and stderr are the same. Since we have no filesystem,
 *          open will only return an error.
 */
int
write (int fd, char* buf, int nbytes)
	/*
       int fd;
       char *buf;
       int nbytes;
       */
{
  int i;

  for (i = 0; i < nbytes; i++) {
    if (*(buf + i) == '\n') {
      outbyte ('\r');
    }
    outbyte (*(buf + i));
  }
  return (nbytes);
}