55 lines
1.6 KiB
C++
55 lines
1.6 KiB
C++
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// fiopen -- _Fiopen(const char *, ios_base::openmode)
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#include <fstream>
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_STD_BEGIN
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_CRTIMP2 FILE *__cdecl _Fiopen(const char *filename, ios_base::openmode mode)
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{ // open a file
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static const char *mods[] =
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{ // fopen mode strings corresponding to valid[i]
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"r", "w", "w", "a", "rb", "wb", "wb", "ab",
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"r+", "w+", "a+", "r+b", "w+b", "a+b", 0};
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static const int valid[] =
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{ // valid combinations of open flags
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ios_base::in,
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ios_base::out,
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ios_base::out | ios_base::trunc,
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ios_base::out | ios_base::app,
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ios_base::in | ios_base::binary,
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ios_base::out | ios_base::binary,
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ios_base::out | ios_base::trunc | ios_base::binary,
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ios_base::out | ios_base::app | ios_base::binary,
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ios_base::in | ios_base::out,
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ios_base::in | ios_base::out | ios_base::trunc,
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ios_base::in | ios_base::out | ios_base::app,
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ios_base::in | ios_base::out | ios_base::binary,
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ios_base::in | ios_base::out | ios_base::trunc
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| ios_base::binary,
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ios_base::in | ios_base::out | ios_base::app
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| ios_base::binary,
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0};
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FILE *fp;
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int n;
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ios_base::openmode atendflag = mode & ios_base::ate;
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mode &= ~ios_base::ate;
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for (n = 0; valid[n] != 0 && valid[n] != mode; ++n)
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; // look for a valid mode
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if (valid[n] == 0 || (fp = fopen(filename, mods[n])) == 0)
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return (0); // no valid mode or open failed
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if (!atendflag || fseek(fp, 0, SEEK_END) == 0)
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return (fp); // no need to seek to end, or seek succeeded
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fclose(fp); // can't position at end
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return (0);
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}
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_STD_END
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/*
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* Copyright (c) 1992-2001 by P.J. Plauger. ALL RIGHTS RESERVED.
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* Consult your license regarding permissions and restrictions.
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V3.10:0009 */
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