4.3BSD - /usr/src/lib/libc/stdio/fdopen.c

   1: /*
   2:  * Copyright (c) 1980 Regents of the University of California.
   3:  * All rights reserved.  The Berkeley software License Agreement
   4:  * specifies the terms and conditions for redistribution.
   5:  */
   6: 
   7: #if defined(LIBC_SCCS) && !defined(lint)
   8: static char sccsid[] = "@(#)fdopen.c	5.2 (Berkeley) 3/9/86";
   9: #endif LIBC_SCCS and not lint
  10: 
  11: /*
  12:  * Unix routine to do an "fopen" on file descriptor
  13:  * The mode has to be repeated because you can't query its
  14:  * status
  15:  */
  16: 
  17: #include <sys/types.h>
  18: #include <sys/file.h>
  19: #include <stdio.h>
  20: 
  21: FILE *
  22: fdopen(fd, mode)
  23:     register char *mode;
  24: {
  25:     extern FILE *_findiop();
  26:     static int nofile = -1;
  27:     register FILE *iop;
  28: 
  29:     if (nofile < 0)
  30:         nofile = getdtablesize();
  31: 
  32:     if (fd < 0 || fd >= nofile)
  33:         return (NULL);
  34: 
  35:     iop = _findiop();
  36:     if (iop == NULL)
  37:         return (NULL);
  38: 
  39:     iop->_cnt = 0;
  40:     iop->_file = fd;
  41:     iop->_bufsiz = 0;
  42:     iop->_base = iop->_ptr = NULL;
  43: 
  44:     switch (*mode) {
  45:     case 'r':
  46:         iop->_flag = _IOREAD;
  47:         break;
  48:     case 'a':
  49:         lseek(fd, (off_t)0, L_XTND);
  50:         /* fall into ... */
  51:     case 'w':
  52:         iop->_flag = _IOWRT;
  53:         break;
  54:     default:
  55:         return (NULL);
  56:     }
  57: 
  58:     if (mode[1] == '+')
  59:         iop->_flag = _IORW;
  60: 
  61:     return (iop);
  62: }

Defined functions

Defined variables