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FUNNELWEB MANUAL WEB PAGE
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Copyright (c) Ross N. Williams 1992,1999. All rights reserved.
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any medium, with or without modification, provided that all
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modifications since the manual's original release by Ross N.
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Williams (www.ross.net) consist of translations or other
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transformations that alter only the manual's form, not its
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content. THIS MANUAL IS PROVIDED "AS IS" AND WITHOUT ANY
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<TITLE>3.1 Basic Input File Processing</TITLE>
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<A HREF="index.html"><FONT COLOR="#FFFFFF"><B>Reference</B></FONT></A><BR>
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<A HREF="intro.html"><FONT COLOR="#FFFFFF">1 Introduction</FONT></A><BR>
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<A HREF="interface.html"><FONT COLOR="#FFFFFF">2 Interface</FONT></A><BR>
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<A HREF="scanner.html"><FONT COLOR="#FFFFFF">3 Scanner</FONT></A><BR>
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<P><FONT SIZE="5">3.1 Basic Input File Processing</FONT><BR>
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<P>In order to read in an input file or include file, the
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scanner calls a submodule called the <STRONG>mapper</STRONG>
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that reads a file in and creates a contiguous copy of it in
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memory. The scanner then performs three checks on the file,
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the first (file termination) of which is performed before
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scanning commences, and the other two of which take place
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during scanning before each line is scanned.
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<P><BLOCKQUOTE><B>File
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Termination:</B> The first check the
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scanner makes is whether the file
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is terminated properly. A file is considered to be properly
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terminated if it either contains no lines, or if the last
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line in the file is terminated by an end-of-line marker. If
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the scanner detects that an input file is not properly
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terminated, it adds an end-of-line marker itself (to the
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copy in memory only).</BLOCKQUOTE>
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<P><BLOCKQUOTE><B>Unprintable Characters:</B> The second check
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the scanner makes is for
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unprintable characters (ASCII 0--31 and 127--255 (except for
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EOL(10))) which it flags as errors and replaces by question
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<P><BLOCKQUOTE><B>Line Lengths:</B> The third check the scanner
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makes is input line length. When
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FunnelWeb starts up, a default maximum input line length of
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80 is set. This can be changed dynamically during scanning
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using a <SAMP>@p maximum_input_line_length</SAMP> pragma. If
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the number of characters on a line (not including the end of
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line marker) exceeds this limit, FunnelWeb generates an
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<A HREF="copyright.html">Copyright © Ross N. Williams 1992,1999. All rights reserved.</A><BR>
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