Request information, resulting from an HTTP POST, is available
via the params vector. The
params vector is always available for the purpose in a VSP context.
Similarly the lines and
path vectors are available
for the HTTP headers and URL path respectively.
Parameters stored in the params vector are stored in
keyword-value pairs, such that keywords are stored in the even
elements, values in the odd numbered elements. Vectors and arrays
can be accessed using the aref() and
aset() functions, however, the exact
position of parameters is seldom known. The get_keyword() function can be used to return the
value of a given parameter. You can specify a default value to
return in case the parameter you are looking for is not found.
Sometimes a POST can supply a large amount of data, such as from
an <INPUT type="file">. When the length of the parameter data
exceeds 5,000,000 octets the result is stored as a string session
in the params array. In these cases the value should not be copied
or converted to a string, it is likely to be truncated. The value
should be stored as a BLOB or an external file. When processing
possibly large input fields in a form either the fourth parameter
should be set to 1 or they should be accessed through aref_set_0() .