Handles
Summary
CFS &01-&02 SRAMFS &16-&18 DOSFS &40-&47 LINKFS &A0-&AF ROMFS &03 HADFS &19-&1D VFS &50-&59 BEEBITFS &B0-&BF TFS &0E-&0F LanManFS &20-&23 RAMFS &60-&64 COPROFS &C0-&CC VaxHostFS &0E-&0F NFS &20-&27 ARAMFS &60-&65 IEEEFS &F0-&FF DFS &11-&15 ANFS &20-&2F HOSTFS &80-&9F NEXUSFS HDFS &12-&17 ADFS &30-&39 IOFS &80-&9F
Full List
&00 0 No opened file &50 80 VFS &B0 176 BeebItFS, BeebLink &01 1 CFS (in) &51 81 VFS &B1 177 BeebItFS, BeebLink &02 2 CFS (out) &52 82 VFS &B2 178 BeebItFS, BeebLink &03 3 ROMFS &53 83 VFS &B3 179 BeebItFS, BeebLink &04 4 &54 84 VFS &B4 180 BeebItFS, BeebLink &05 5 &55 85 VFS &B5 181 BeebItFS, BeebLink &06 6 &56 86 VFS &B6 182 BeebItFS, BeebLink &07 7 &57 87 VFS &B7 183 BeebItFS, BeebLink &08 8 &58 88 VFS &B8 184 BeebItFS, BeebLink &09 9 &59 89 VFS &B9 185 BeebItFS, BeebLink &0A 10 &5A 80 &BA 186 BeebItFS, BeebLink &0B 11 &5B 91 &BB 187 BeebItFS, BeebLink &0C 12 &5C 92 &BC 188 BeebItFS, BeebLink &0D 13 &5D 93 &BD 189 BeebItFS, BeebLink &0E 14 TFS, VaxHostFS &5E 94 &BE 190 BeebItFS, BeebLink &0F 15 TFS, VaxHostFS &5F 95 &BF 191 BeebItFS, BeebLink &10 16 &60 96 Acacia RAMFS, RAMFS &C0 192 COPROFS &11 17 DFS &61 97 Acacia RAMFS, RAMFS &C1 193 COPROFS &12 18 DFS, HDFS &62 98 Acacia RAMFS, RAMFS &C2 194 COPROFS &13 19 DFS, HDFS &63 99 Acacia RAMFS, RAMFS &C3 195 COPROFS &14 20 DFS, HDFS &64 100 Acacia RAMFS, RAMFS &C4 196 COPROFS &15 21 DFS, HDFS &65 101 Acacia RAMFS &C5 197 COPROFS &16 22 Sprow RAMFS, HDFS &66 102 &C6 198 COPROFS &17 23 Sprow RAMFS, HDFS &67 103 &C7 199 COPROFS &18 24 Sprow RAMFS .. &C8 200 COPROFS &19 25 HADFS .. &C9 201 COPROFS &1A 26 HADFS &7A 122 &CA 202 COPROFS &1B 27 HADFS &7B 123 &CB 203 COPROFS &1C 28 HADFS &7C 124 &CC 204 COPROFS &1D 29 HADFS &7D 125 &CD 205 &1E 30 &7E 126 &CE 206 &1F 31 &7F 127 &CF 207 &20 32 NFS, ANFS, LanManFS &80 128 IOFS, HostFS &D0 208 &21 33 NFS, ANFS, LanManFS &81 129 IOFS, HostFS &D1 209 &22 34 NFS, ANFS, LanManFS &82 130 IOFS, HostFS &D2 210 &23 35 NFS, ANFS, LanManFS &83 131 IOFS, HostFS &D3 211 &24 36 NFS, ANFS &84 132 IOFS, HostFS &D4 212 &25 37 NFS, ANFS &85 133 IOFS, HostFS &D5 213 &26 38 NFS, ANFS &86 134 IOFS, HostFS &D6 214 &27 39 NFS, ANFS &87 135 IOFS, HostFS &D7 215 &28 40 ANFS &88 136 IOFS, HostFS &D8 216 &29 41 ANFS &89 137 IOFS, HostFS &D9 217 &2A 42 ANFS &8A 138 IOFS, HostFS &DA 218 &2B 43 ANFS &8B 139 IOFS, HostFS &DB 219 &2C 44 ANFS &8C 140 IOFS, HostFS &DC 220 &2D 45 ANFS &8D 141 IOFS, HostFS &DD 221 &2E 46 ANFS &8E 142 IOFS, HostFS &DE 222 &2F 47 ANFS &8F 143 IOFS, HostFS &DF 223 &30 48 ADFS &90 144 IOFS, HostFS &E0 224 &31 49 ADFS &91 145 IOFS, HostFS &E1 225 &32 50 ADFS &92 146 IOFS, HostFS &E2 226 &33 51 ADFS &93 147 IOFS, HostFS &E3 227 &34 52 ADFS &94 148 IOFS, HostFS &E4 228 &35 53 ADFS &95 149 IOFS, HostFS &E5 229 &36 54 ADFS &96 150 IOFS, HostFS &E6 230 &37 55 ADFS &97 151 IOFS, HostFS &E7 231 &38 56 ADFS &98 152 IOFS, HostFS &E8 232 &39 57 ADFS &99 153 IOFS, HostFS &E9 233 &3A 58 &9A 154 IOFS, HostFS &EA 234 &3B 59 &9B 155 IOFS, HostFS &EB 235 &3C 60 &9C 156 IOFS, HostFS &EC 236 &3D 61 &9D 157 IOFS, HostFS &ED 237 &3E 62 &9E 158 IOFS, HostFS &EE 238 &3F 63 &9F 159 IOFS, HostFS &EF 239 &40 64 DOSFS &A0 160 LFS, BeebLink* &F0 240 IEEEFS &41 65 DOSFS &A1 161 LFS, BeebLink* &F1 241 IEEEFS &42 66 DOSFS &A2 162 LFS, BeebLink* &F2 242 IEEEFS &43 67 DOSFS &A3 163 LFS, BeebLink* &F3 243 IEEEFS &44 68 DOSFS &A4 164 LFS, BeebLink* &F4 244 IEEEFS &45 69 DOSFS &A5 165 LFS, BeebLink* &F5 245 IEEEFS &46 70 DOSFS &A6 166 LFS, BeebLink* &F6 246 IEEEFS &47 71 DOSFS &A7 167 LFS, BeebLink* &F7 247 IEEEFS &48 72 &A8 168 LFS, BeebLink* &F8 248 IEEEFS &49 73 &A9 169 LFS, BeebLink* &F9 249 IEEEFS &4A 74 &AA 170 LFS, BeebLink* &FA 250 IEEEFS &4B 75 &AB 171 LFS, BeebLink* &FB 251 IEEEFS &4C 76 &AC 172 LFS, BeebLink* &FC 252 IEEEFS &4D 77 &AD 173 LFS, BeebLink* &FD 253 IEEEFS &4E 78 &AE 174 LFS, BeebLink* &FE 254 IEEEFS &4F 79 &AF 175 LFS, BeebLink* &FF 255 IEEEFS
Special cases
When reading PTR and EXT from 8-bit BASIC, the data parameter is BASIC's integer store, which will be set to the channel as the last item evaluated. That means that PTR#0 and EXT#0 pass a data value of zero; OSARGS 0,0 and OSARGS 2,0 do not change the data word; this means that in 8-bit BASICs PTR#0 and EXT#0 return zero, being the unchanged data word set to the channel.
This means that other BASICs have the ability to use PTR#0 and EXT#0 to return information specific to that implementation. Some BASICs or operating systems allow other special handles to return specific information.
- The most common case is that channel 0 references the console, ie the keyboard and VDU:
- OSBGET#0 reads from OSRDCH
- OSBPUT#0 writes to OSWRCH
- EOF#0 returns TRUE if the next OSBGET#0 or OSRDCH/GET/INKEY will not return a character without waiting, ie
IF NOT EOF#0 THEN key%=GET - PTR#0 returns platform-specific information
- EXT#0 returns platform-specific information
- Some C compilers implement C console handles:
- Reading from channel 0 reads from STDIN (via OSRDCH)
- Writing to channel 1 writes to STDOUT (via OSWRCH)
- Writing to channel 2 writes to STDERR (via OSWRCH).
Known implementations
| Implemented at the operating system layer |
BGET#0 | BPUT#0 | OSGBPB#0 | EOF#0 | PTR#0 | EXT#0 |
|---|---|---|---|---|---|---|
| BBC MOS and CoPros | untested | untested | error or -1 | 0 | 0 | |
| ARM Development System[1] | |
|
|
untested | untested | untested |
| PDP11 CoPro | OSRDCH[2] | OSWRCH[2] | untested | untested | untested | |
| TubeHost | OSRDCH | OSWRCH | 0 if keypress pending | untested | untested | |
| Implemented by BASIC | BGET#0 | BPUT#0 | EOF#0 | PTR#0 | EXT#0 | |
| Windows BASIC | untested | untested | untested | untested | untested | |
| Brandy Basic | ||||||
| Others | BGET#-1 | BPUT#-1 | EOF#-1 | PTR#-1 | EXT#-1 | |
| Sinclair Z88 | untested | untested | 0=unexpanded, -1=expanded | b0-b15=ROM version, b16=b31=number of handles remaining |
amount of free system memory |
[1] I'm sure there is an ARM system that does this, needs further investigation
[2] Build option
Notes
CoProFS is documented as using &C0-&C4, but actually will use as many as its workspace allows, up to &C0-&CC.
RetroClinic RAMFS uses &60-&64, Acacia RAMFS uses &60-&65.
Early versions of HADFS used &05-&0A and &85-&8A to read/write control information, later versions use &19-&1D to access this control information.
IOFS in BBCTerm uses handles &80-&9F but its OSFSC entry reports that it uses &80-&A0. IOFS also incorrectly reports its filing system number as &00.
LanManFS clashes with NFS/ANFS, but the hardware cannot be present at the same time as the LanManFS Ethernet card plugs into the Econet card sockets.
BeebLink* entries are used by the BeebLink Test FS ROM, which can coexist with the ordinary BeebLink ROM while testing.
References
- Advanced BBC User Guide
- New Advanced BBC User Guide
- Advanced Electron User Guide (RAMFS)
- http://mdfs.net/Docs/Comp/BBC/Filing/Handles
Jgharston 22:14, 1 September 2007 (BST)
