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<TITLE>8.5 How a Command Line is Processed</TITLE>
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<P><FONT SIZE="5">8.5 How a Command Line is Processed</FONT><BR>
<P>When FunnelWeb reads in a command line (from the
console or a script file), it processes it in the following
sequence:
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<LI> The command line is checked for non-printable
characters. If there are any, they are flagged with a severe
error.
<LI> All dollar string substitution variables in the
command line are replaced by their corresponding string. The
command line is processed from left to right. Substitutions
are performed non recursively.
<LI> At this point, if the line is empty, or consists
entirely of blanks, it is ignored and the interpreter moves
to the next line.
<LI> A severe error is generated if the line at this
stage begins with a blank.
<LI> If the first character of the line is "<TT>!</TT>",
the line is a comment line and is ignored.
<LI> The run of non-blanks commencing at the start of the
line is compared case-insensitively to each of the legal
command verbs. If the command is illegal, a severe error is
generated, otherwise the command is processed.
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