| ??? 11/08/07 16:17 Modified: 11/08/07 16:26 Read: times |
#146782 - Function pointers and stuff Responding to: ???'s previous message |
As this is a re-post of an existing topic, you should give a link to what's been said already:
http://www.8052.com/forum/read.phtml?id=146774 Please also look at the instructions on how to post source code, and note the 'Insert Code' button: http://www.8052.com/faqs.phtml?FAQ=120199 Cyrille Ngassam said:
I know that in C is pointers important fur speed. No, that's not true. In any language, indirection will always be slower than direct access! I agree that for variable are pointers important but why therefor use pointers to function? You'd use a function pointer where you didn't know what function you'll be calling at compile time. eg, they are commonly used for Call-backs in APIs, Operating Systems, etc. Another common use is in Tables of Function pointers to implement finite state machines I tought the same of pointers of pointers. why and when must we use pointers of pointers ? There's no compulsion about it - you just use them where they provide the most appropriate solution to the problem at hand! here ist an exemple : That looks like an example of a linked-list - nothing to do with function pointers there? Take a look at this thread: http://www.keil.com/forum/docs/thread11072.asp See also: http://www.8052.com/forum/read.phtml?id=146784 |
| Topic | Author | Date |
| C : pointers of function und pointers of pointers | 01/01/70 00:00 | |
| Function pointers and stuff | 01/01/70 00:00 | |
| Parameter passing in C | 01/01/70 00:00 | |
| C FAQ | 01/01/70 00:00 | |
| Function pointer demo | 01/01/70 00:00 | |
| Heads up | 01/01/70 00:00 | |
| True | 01/01/70 00:00 | |
| I use function pointers all the time | 01/01/70 00:00 | |
| void-void function pointers need not be slow | 01/01/70 00:00 | |
| correct, with a caveat | 01/01/70 00:00 | |
thank you all. | 01/01/70 00:00 |