Chapter 18. The Specialized C API for PLplot

Table of Contents
plP_checkdriverinit: Checks to see if any of the specified drivers have been initialized
plP_getinitdriverlist: Get the initialized-driver list
plabort: Error abort
plexit: Error exit
plgfile: Get output file handle
plsabort: Set abort handler
plsexit: Set exit handler
plsfile: Set output file handle
pltr0: Identity transformation for grid to world mapping
pltr1: Linear interpolation for grid to world mapping using singly dimensioned coord arrays
pltr2: Linear interpolation for grid to world mapping using doubly dimensioned coord arrays (column dominant, as per normal C 2d arrays)

The purpose of this chapter is to document the API for every C function in PLplot (other than language bindings) that is not part of the common API that has already been documented in Chapter 17.

This chapter is a work that is just starting. There are many C functions in the code base that are not part of the common API, and we haven't even gotten to the point of listing them all. What gets documented here now is whatever C-explicit code we are trying to understand at the time.

plP_checkdriverinit: Checks to see if any of the specified drivers have been initialized

plP_checkdriverinit (list);

Checks to see if any of the specified drivers have been initialized. Function tests a space-delimited list of driver names to see how many of the given drivers have been initialized, and how often. The return code of the function is: 0 if no matching drivers were found to have been initialized; -1 if an error occurred allocating the internal buffer; or, a positive number indicating the number of streams encountered that belong to drivers on the provided list. This function invokes plP_getinitdriverlist internally to get a complete list of drivers that have been initialized in order to compare with the driver names specified in the argument list to plP_checkdriverinit.

list (char *, input)

Pointer to character string specifying a space-delimited list of driver names, e.g., "bmp jpeg tiff".