Chapter 23. Internal C functions in PLplot
Prev | Part IV. Reference | Next

## Chapter 23. Internal C functions in PLplot

The purpose of this chapter is to document the API for every internal C function in PLplot (other than language bindings) that is not part of the common API that has already been documented in Chapter 18, The Common API for PLplot or elsewhere. The functions documented here are internal plplot functions. They are not intended for external use and may change between releases.

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"`.

Prev | Up | Next
`plwid`: Set pen width | Home | `plP_getinitdriverlist`: Get the initialized-driver list