Home » Recent acquisitions » Acorn ADFS disks » adfs_ArchimedesWorld_199201.adf » January92 » !AWJan92/Goodies/FindDir/!FindDir/DevNotes
!AWJan92/Goodies/FindDir/!FindDir/DevNotes
This website contains an archive of files for the Acorn Electron, BBC Micro, Acorn Archimedes, Commodore 16 and Commodore 64 computers, which Dominic Ford has rescued from his private collection of floppy disks and cassettes.
Some of these files were originally commercial releases in the 1980s and 1990s, but they are now widely available online. I assume that copyright over them is no longer being asserted. If you own the copyright and would like files to be removed, please contact me.
| Tape/disk: | Home » Recent acquisitions » Acorn ADFS disks » adfs_ArchimedesWorld_199201.adf » January92 |
| Filename: | !AWJan92/Goodies/FindDir/!FindDir/DevNotes |
| Read OK: | ✔ |
| File size: | 05B0 bytes |
| Load address: | 0000 |
| Exec address: | 0000 |
File contents
Development Notes _________________ - fopen() seems to have behave strange especially with floppy discs. When ADFS tries to remove a discname i.e when all eight disc names have been used and you add a ninth disc it causes fopen to crash FileCore sometimes (on both read & write). To overcome this use whenever possible RISC OS read/write file functions. fopen() also requires min 32K free on a disc when it creates a file to write to. N.B This program was developed with Clib version 3.50, later versions may correct this bug. - When using flex it grabs memory above what you set using wimpslot. Large memory requests also seem in some cases to require a much larger memory overhead (over what you actually request) than small memory requests. - Message handling is not explained very well in the Prog's reference manual. When using User_Message_Recorded, if no one accepted your message you're program will recieve a User_Message_Acknowledged, else User_Message is sent (in most cases). - Since you can't use asd with RISC OS progs you either have to use werr or you can write debug info to a file. If you use fopen remember to use setvbuf with _IONBF since if you're program crashes all you're debug info will be written to file. It will slow I/O however. - For sorting use qsort() wherever possible as it is one of the fastest algorithms. For finding an item in a sorted list there is bsearch() which is a reasonably fast search alogorithm.
00000000 0a 20 44 65 76 65 6c 6f 70 6d 65 6e 74 20 4e 6f |. Development No| 00000010 74 65 73 0a 20 5f 5f 5f 5f 5f 5f 5f 5f 5f 5f 5f |tes. ___________| 00000020 5f 5f 5f 5f 5f 5f 0a 0a 20 2d 20 66 6f 70 65 6e |______.. - fopen| 00000030 28 29 20 73 65 65 6d 73 20 74 6f 20 68 61 76 65 |() seems to have| 00000040 20 62 65 68 61 76 65 20 73 74 72 61 6e 67 65 20 | behave strange | 00000050 65 73 70 65 63 69 61 6c 6c 79 20 77 69 74 68 20 |especially with | 00000060 66 6c 6f 70 70 79 20 64 69 73 63 73 2e 20 57 68 |floppy discs. Wh| 00000070 65 6e 0a 41 44 46 53 20 74 72 69 65 73 20 74 6f |en.ADFS tries to| 00000080 20 72 65 6d 6f 76 65 20 61 20 64 69 73 63 6e 61 | remove a discna| 00000090 6d 65 20 69 2e 65 20 77 68 65 6e 20 61 6c 6c 20 |me i.e when all | 000000a0 65 69 67 68 74 20 64 69 73 63 20 6e 61 6d 65 73 |eight disc names| 000000b0 20 68 61 76 65 20 62 65 65 6e 20 75 73 65 64 0a | have been used.| 000000c0 61 6e 64 20 79 6f 75 20 61 64 64 20 61 20 6e 69 |and you add a ni| 000000d0 6e 74 68 20 64 69 73 63 20 69 74 20 63 61 75 73 |nth disc it caus| 000000e0 65 73 20 66 6f 70 65 6e 20 74 6f 20 63 72 61 73 |es fopen to cras| 000000f0 68 20 46 69 6c 65 43 6f 72 65 20 73 6f 6d 65 74 |h FileCore somet| 00000100 69 6d 65 73 20 28 6f 6e 0a 62 6f 74 68 20 72 65 |imes (on.both re| 00000110 61 64 20 26 20 77 72 69 74 65 29 2e 20 54 6f 20 |ad & write). To | 00000120 6f 76 65 72 63 6f 6d 65 20 74 68 69 73 20 75 73 |overcome this us| 00000130 65 20 77 68 65 6e 65 76 65 72 20 70 6f 73 73 69 |e whenever possi| 00000140 62 6c 65 20 52 49 53 43 20 4f 53 0a 72 65 61 64 |ble RISC OS.read| 00000150 2f 77 72 69 74 65 20 66 69 6c 65 20 66 75 6e 63 |/write file func| 00000160 74 69 6f 6e 73 2e 20 66 6f 70 65 6e 28 29 20 61 |tions. fopen() a| 00000170 6c 73 6f 20 72 65 71 75 69 72 65 73 20 6d 69 6e |lso requires min| 00000180 20 33 32 4b 20 66 72 65 65 20 6f 6e 20 61 20 64 | 32K free on a d| 00000190 69 73 63 20 77 68 65 6e 0a 69 74 20 63 72 65 61 |isc when.it crea| 000001a0 74 65 73 20 61 20 66 69 6c 65 20 74 6f 20 77 72 |tes a file to wr| 000001b0 69 74 65 20 74 6f 2e 20 4e 2e 42 20 54 68 69 73 |ite to. N.B This| 000001c0 20 70 72 6f 67 72 61 6d 20 77 61 73 20 64 65 76 | program was dev| 000001d0 65 6c 6f 70 65 64 20 77 69 74 68 20 43 6c 69 62 |eloped with Clib| 000001e0 0a 76 65 72 73 69 6f 6e 20 33 2e 35 30 2c 20 6c |.version 3.50, l| 000001f0 61 74 65 72 20 76 65 72 73 69 6f 6e 73 20 6d 61 |ater versions ma| 00000200 79 20 63 6f 72 72 65 63 74 20 74 68 69 73 20 62 |y correct this b| 00000210 75 67 2e 0a 0a 20 2d 20 57 68 65 6e 20 75 73 69 |ug... - When usi| 00000220 6e 67 20 66 6c 65 78 20 69 74 20 67 72 61 62 73 |ng flex it grabs| 00000230 20 6d 65 6d 6f 72 79 20 61 62 6f 76 65 20 77 68 | memory above wh| 00000240 61 74 20 79 6f 75 20 73 65 74 20 75 73 69 6e 67 |at you set using| 00000250 20 77 69 6d 70 73 6c 6f 74 2e 20 4c 61 72 67 65 | wimpslot. Large| 00000260 0a 6d 65 6d 6f 72 79 20 72 65 71 75 65 73 74 73 |.memory requests| 00000270 20 61 6c 73 6f 20 73 65 65 6d 20 69 6e 20 73 6f | also seem in so| 00000280 6d 65 20 63 61 73 65 73 20 74 6f 20 72 65 71 75 |me cases to requ| 00000290 69 72 65 20 61 20 6d 75 63 68 20 6c 61 72 67 65 |ire a much large| 000002a0 72 20 6d 65 6d 6f 72 79 0a 6f 76 65 72 68 65 61 |r memory.overhea| 000002b0 64 20 28 6f 76 65 72 20 77 68 61 74 20 79 6f 75 |d (over what you| 000002c0 20 61 63 74 75 61 6c 6c 79 20 72 65 71 75 65 73 | actually reques| 000002d0 74 29 20 74 68 61 6e 20 73 6d 61 6c 6c 20 6d 65 |t) than small me| 000002e0 6d 6f 72 79 20 72 65 71 75 65 73 74 73 2e 0a 0a |mory requests...| 000002f0 20 2d 20 4d 65 73 73 61 67 65 20 68 61 6e 64 6c | - Message handl| 00000300 69 6e 67 20 69 73 20 6e 6f 74 20 65 78 70 6c 61 |ing is not expla| 00000310 69 6e 65 64 20 76 65 72 79 20 77 65 6c 6c 20 69 |ined very well i| 00000320 6e 20 74 68 65 20 50 72 6f 67 27 73 20 72 65 66 |n the Prog's ref| 00000330 65 72 65 6e 63 65 0a 6d 61 6e 75 61 6c 2e 20 57 |erence.manual. W| 00000340 68 65 6e 20 75 73 69 6e 67 20 55 73 65 72 5f 4d |hen using User_M| 00000350 65 73 73 61 67 65 5f 52 65 63 6f 72 64 65 64 2c |essage_Recorded,| 00000360 20 69 66 20 6e 6f 20 6f 6e 65 20 61 63 63 65 70 | if no one accep| 00000370 74 65 64 20 79 6f 75 72 20 6d 65 73 73 61 67 65 |ted your message| 00000380 0a 79 6f 75 27 72 65 20 70 72 6f 67 72 61 6d 20 |.you're program | 00000390 77 69 6c 6c 20 72 65 63 69 65 76 65 20 61 20 55 |will recieve a U| 000003a0 73 65 72 5f 4d 65 73 73 61 67 65 5f 41 63 6b 6e |ser_Message_Ackn| 000003b0 6f 77 6c 65 64 67 65 64 2c 20 65 6c 73 65 20 55 |owledged, else U| 000003c0 73 65 72 5f 4d 65 73 73 61 67 65 0a 69 73 20 73 |ser_Message.is s| 000003d0 65 6e 74 20 28 69 6e 20 6d 6f 73 74 20 63 61 73 |ent (in most cas| 000003e0 65 73 29 2e 0a 0a 20 2d 20 53 69 6e 63 65 20 79 |es)... - Since y| 000003f0 6f 75 20 63 61 6e 27 74 20 75 73 65 20 61 73 64 |ou can't use asd| 00000400 20 77 69 74 68 20 52 49 53 43 20 4f 53 20 70 72 | with RISC OS pr| 00000410 6f 67 73 20 79 6f 75 20 65 69 74 68 65 72 20 68 |ogs you either h| 00000420 61 76 65 20 74 6f 20 75 73 65 20 77 65 72 72 20 |ave to use werr | 00000430 6f 72 0a 79 6f 75 20 63 61 6e 20 77 72 69 74 65 |or.you can write| 00000440 20 64 65 62 75 67 20 69 6e 66 6f 20 74 6f 20 61 | debug info to a| 00000450 20 66 69 6c 65 2e 20 49 66 20 79 6f 75 20 75 73 | file. If you us| 00000460 65 20 66 6f 70 65 6e 20 72 65 6d 65 6d 62 65 72 |e fopen remember| 00000470 20 74 6f 20 75 73 65 20 73 65 74 76 62 75 66 0a | to use setvbuf.| 00000480 77 69 74 68 20 5f 49 4f 4e 42 46 20 73 69 6e 63 |with _IONBF sinc| 00000490 65 20 69 66 20 79 6f 75 27 72 65 20 70 72 6f 67 |e if you're prog| 000004a0 72 61 6d 20 63 72 61 73 68 65 73 20 61 6c 6c 20 |ram crashes all | 000004b0 79 6f 75 27 72 65 20 64 65 62 75 67 20 69 6e 66 |you're debug inf| 000004c0 6f 20 77 69 6c 6c 20 62 65 0a 77 72 69 74 74 65 |o will be.writte| 000004d0 6e 20 74 6f 20 66 69 6c 65 2e 20 49 74 20 77 69 |n to file. It wi| 000004e0 6c 6c 20 73 6c 6f 77 20 49 2f 4f 20 68 6f 77 65 |ll slow I/O howe| 000004f0 76 65 72 2e 0a 0a 20 2d 20 46 6f 72 20 73 6f 72 |ver... - For sor| 00000500 74 69 6e 67 20 75 73 65 20 71 73 6f 72 74 28 29 |ting use qsort()| 00000510 20 77 68 65 72 65 76 65 72 20 70 6f 73 73 69 62 | wherever possib| 00000520 6c 65 20 61 73 20 69 74 20 69 73 20 6f 6e 65 20 |le as it is one | 00000530 6f 66 20 74 68 65 20 66 61 73 74 65 73 74 0a 61 |of the fastest.a| 00000540 6c 67 6f 72 69 74 68 6d 73 2e 20 46 6f 72 20 66 |lgorithms. For f| 00000550 69 6e 64 69 6e 67 20 61 6e 20 69 74 65 6d 20 69 |inding an item i| 00000560 6e 20 61 20 73 6f 72 74 65 64 20 6c 69 73 74 20 |n a sorted list | 00000570 74 68 65 72 65 20 69 73 20 62 73 65 61 72 63 68 |there is bsearch| 00000580 28 29 20 77 68 69 63 68 20 69 73 20 61 0a 72 65 |() which is a.re| 00000590 61 73 6f 6e 61 62 6c 79 20 66 61 73 74 20 73 65 |asonably fast se| 000005a0 61 72 63 68 20 61 6c 6f 67 6f 72 69 74 68 6d 2e |arch alogorithm.| 000005b0
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