57 lines
1.9 KiB
C
57 lines
1.9 KiB
C
/* Retrieve information about a FILE stream.
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Copyright (C) 2007, 2009-2022 Free Software Foundation, Inc.
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This file is free software: you can redistribute it and/or modify
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it under the terms of the GNU Lesser General Public License as
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published by the Free Software Foundation, either version 3 of the
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License, or (at your option) any later version.
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This file is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU Lesser General Public License for more details.
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You should have received a copy of the GNU Lesser General Public License
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along with this program. If not, see <https://www.gnu.org/licenses/>. */
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#include <stdbool.h>
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#include <stdio.h>
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/* Return true if the stream STREAM is opened write-only or
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append-only, or if the last operation on the stream was a write
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operation. Return false if the stream is opened read-only, or if
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it supports reading and there is no current write operation (such
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as fputc).
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freading and fwriting will never both be true. If STREAM supports
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both reads and writes, then:
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- both freading and fwriting might be false when the stream is first
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opened, after read encounters EOF, or after fflush,
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- freading might be false or true and fwriting might be false
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after repositioning (such as fseek, fsetpos, or rewind),
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depending on the underlying implementation.
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STREAM must not be wide-character oriented. */
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#if HAVE___FWRITING
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/* glibc >= 2.2, Solaris >= 7, UnixWare >= 7.1.4.MP4, Cygwin >= 1.7.34, Android API >= 29, musl libc */
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# if HAVE_STDIO_EXT_H
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# include <stdio_ext.h>
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# endif
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# define fwriting(stream) (__fwriting (stream) != 0)
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#else
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# ifdef __cplusplus
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extern "C" {
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# endif
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extern bool fwriting (FILE *stream) _GL_ATTRIBUTE_PURE;
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# ifdef __cplusplus
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}
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# endif
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#endif
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