Gescapes

The hpsbv driver recognizes a number of gescape functions. Following are the supported functions and definitions. Details can be found in Appendix A of this manual.

SBVESC_OBJ_NAME — Name the following data by this name.
SBVESC_BEGIN_ARC — Begin archiving all relevant Starbase calls.
SBVESC_END_ARC — Stop archiving any future Starbase calls.
SBVESC_COMMENT — Embed a user-defined comment in the archive file (has no effect on output object data).
SBVESC_LF_COORD — Left handed coordinate data.
SBVESC_RT_COORD — Right handed coordinate data.

Gescape Syntax

The gescape function allows the application program to input or output to a device in a device dependent manner. The C syntax for the gescape function is:

/* gescape_arg is typedef defined in starbase.c.h */
 
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gescape_arg arg1, arg2;
 
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gescape(fildes, 〈op〉, &arg1, &arg2);

Where fildes is the file descriptor of the device to be accessed (returned by Starbase gopen call).

The 〈op〉 is the opcode that specifies the action to be performed. This code is only relevant to a specific driver and is ignored when passed to other devices.

The arg1 and arg2 parameters provide additional data needed by a gescape.

Gescapes

Technical documentation

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Gescape Syntax