If you use the -string syntax, the adp is a string containing ADP syntax to be parsed. Note that when you call ns_adp_parse with the -string syntax from inside an ADP, the string cannot contain the <% ... %> syntax. The -string syntax is the default.
If you use the -file syntax, the adp is the absolute filename of the file containing the ADP to be parsed. The -string syntax is the default.
You can pass optional arguments (arg1, arg2, etc.) to the ADP. The arguments can be accessed within the ADP using the ns_adp_argc, ns_adp_argv, and ns_adp_bind_args functions.
If this call is a nested ADP evaluation (where one ADP calls another), an error will be returned if the maximum number of nested ADP evaluations, 256, has been exceeded.