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10.2 FORM Strings

The format of a FORM string in GNAT is:

     "keyword=value,keyword=value,...,keyword=value"

where letters may be in upper or lower case, and there are no spaces between values. The order of the entries is not important. Currently the following keywords defined.

     TEXT_TRANSLATION=[YES|NO|TEXT|BINARY|U8TEXT|WTEXT|U16TEXT]
     SHARED=[YES|NO]
     WCEM=[n|h|u|s|e|8|b]
     ENCODING=[UTF8|8BITS]

The use of these parameters is described later in this section. If an unrecognized keyword appears in a form string, it is silently ignored and not considered invalid.

For OpenVMS additional FORM string keywords are available for use with RMS services. The syntax is:

     VMS_RMS_Keys=(keyword=value,...,keyword=value)

The following RMS keywords and values are currently defined:

     Context=Force_Stream_Mode|Force_Record_Mode

VMS RMS keys are silently ignored on non-VMS systems. On OpenVMS unimplented RMS keywords, values, or invalid syntax will raise Use_Error.