31 lines
578 B
C
31 lines
578 B
C
/*
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* ungetc.c - push a character back onto an input stream
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*/
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/* $Id$ */
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#include <stdio.h>
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#if ACKCONF_WANT_STDIO && ACKCONF_WANT_EMULATED_FILE
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int ungetc(int ch, FILE* stream)
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{
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unsigned char* p;
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if (ch == EOF || !io_testflag(stream, _IOREADING))
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return EOF;
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if (stream->_ptr == stream->_buf)
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{
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if (stream->_count != 0)
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return EOF;
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stream->_ptr++;
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}
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stream->_count++;
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p = --(stream->_ptr); /* ??? Bloody vax assembler !!! */
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/* ungetc() in sscanf() shouldn't write in rom */
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if (*p != (unsigned char)ch)
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*p = (unsigned char)ch;
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return ch;
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}
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#endif
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