When this entry is called, certain values are available in certain parameter variables, and the current device is the TCP/IP channel that links the M[UMPS] software to the browser of the end-user.
The M[UMPS] program is expected to do "whatever processing is indicated by the values in the parameter variables" and then transmit information to the browser (encoded as a web-page in the HTML language). The latter is facilitated by the fact that the link between the program and the browser is the current device.
In the case of the Macbeth example, the form defines a number of "web" variables:
<form action="macbeth.web" method="POST">
<input type=hidden name="EP" value="FIRST">
<b>Search for</b> <input type=text name="Search" value="">
<b>Select from</b> <select name="Select">
<input type=submit value="Search Database" name="Button"><p>
These variables are passed to the M[UMPS] program in the local
array %:
%("MSMWEB_QUERY","Button") = Search Database
%("MSMWEB_QUERY","EP") = FIRST
%("MSMWEB_QUERY","Search") = an
%("MSMWEB_QUERY","Select") = 1
The first subscript in this array is a constant that identifies the sub-tree of variables that is returned by the most recent form, and the second subscript is the name of the variable, as specified in the form. The value of the array-element is the same as the value of the form-variable. In particular, the value of %("MSMWEB_QUERY","Search") is equal to the text that the end-user entered into the Text Box, and the value of %("MSMWEB_QUERY","Select") is equal to the (internal) code for the value that the end-user selected from the drop down list.
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