projects / unix-history / blame
| Commit | Line | Data |
|---|---|---|
| c9be6cfe KB |
1 | /*- |
| 2 | * Copyright (c) 1990 The Regents of the University of California. | |
| 3 | * All rights reserved. | |
| 4 | * | |
| 5 | * This code is derived from software contributed to Berkeley by | |
| 6 | * Chris Torek. | |
| 7 | * | |
| 8 | * %sccs.include.redist.c% | |
| 9 | */ | |
| 10 | ||
| 11 | #if defined(LIBC_SCCS) && !defined(lint) | |
| 12 | static char sccsid[] = "@(#)fflush.c 5.1 (Berkeley) %G%"; | |
| 13 | #endif /* LIBC_SCCS and not lint */ | |
| 14 | ||
| 15 | #include <sys/errno.h> | |
| 16 | #include <stdio.h> | |
| 17 | #include "local.h" | |
| 18 | ||
| 19 | /* Flush a single file, or (if fp is NULL) all files. */ | |
| 20 | fflush(fp) | |
| 21 | register FILE *fp; | |
| 22 | { | |
| 23 | if (fp == NULL) | |
| 24 | return (_fwalk(__sflush)); | |
| 25 | ||
| 26 | if ((fp->_flags & __SWR) == 0) { | |
| 27 | errno = EBADF; | |
| 28 | return (EOF); | |
| 29 | } | |
| 30 | return (__sflush(fp)); | |
| 31 | } | |
| 32 | ||
| 33 | __sflush(fp) | |
| 34 | register FILE *fp; | |
| 35 | { | |
| 36 | register unsigned char *p; | |
| 37 | register int n, t; | |
| 38 | ||
| 39 | t = fp->_flags; | |
| 40 | if ((t & __SWR) == 0) | |
| 41 | return (0); | |
| 42 | ||
| 43 | if ((p = fp->_bf._base) == NULL) | |
| 44 | return (0); | |
| 45 | ||
| 46 | n = fp->_p - p; /* write this much */ | |
| 47 | ||
| 48 | /* | |
| 49 | * Set these immediately to avoid problems with longjmp and to allow | |
| 50 | * exchange buffering (via setvbuf) in user write function. | |
| 51 | */ | |
| 52 | fp->_p = p; | |
| 53 | fp->_w = t & (__SLBF|__SNBF) ? 0 : fp->_bf._size; | |
| 54 | ||
| 55 | for (; n > 0; n -= t, p += t) { | |
| 56 | t = (*fp->_write)(fp->_cookie, (char *)p, n); | |
| 57 | if (t <= 0) { | |
| 58 | fp->_flags |= __SERR; | |
| 59 | return (EOF); | |
| 60 | } | |
| 61 | } | |
| 62 | return (0); | |
| 63 | } |