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| Temporary feature: subject to change |
Figure 45–1. $queryFileCacheParms
| BOOLEAN PROCEDURE $queryFileCacheParms (POINTER(file) f; OPTIONAL PRODUCES LONG BITS attributes; OPTIONAL PRODUCES LONG INTEGER requestedMinSize, requestedMaxSize, currentSize; OPTIONAL PRODUCES INTEGER requestedHitPercent, currentHitPercent; OPTIONAL BITS ctrlBits); |
$queryFileCacheParms returns information about the cache associated with the file f, except that if f is NULLPOINTER, then information about the global cache is returned. If f is not NULLPOINTER and f cannot be cached, e.g., if it is a sequential, unbuffered, or mapped disk file, an error occurs and $queryFileCacheParms returns FALSE.
If f is a globally cached file or if f is NULLPOINTER, information about the global cache is returned. If f is a privately cached file, information about the private cache is returned. If f is not cached, all PRODUCES parameters are set to Zero and $queryFileCacheParms returns TRUE. The PRODUCES parameters and their meanings are as follows:
| attributes | If f is not NULLPOINTER, then attributes returns information about how the file is cached, i.e., globally cached (the predefined bit $globallyCached is set), privately cached (the predefined bit $privatelyCached is set), or not cached (attributes is Zero). |
| requestedMinSize | The requested minimum number of buffers in the LRU list |
| requestedMaxSize | The requested maximum number of buffers in the LRU list |
| currentSize | The current number of buffers in the LRU list |
| requestedHitPercent | The requested hit percent |
| currentHitPercent | The current hit percent |
The only valid ctrlBits is errorOK. An error message is generated if an error occurs and errorOK is not specified.
Section 22.16 and the description of GCCHP in Chapter 14 of the MAINSAIL Utilities User's Guide tell more about how the file cache works.
MAINSAIL Language Manual, Section 45.1