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OS_FSControl 28
OS SWI Calls
» OS_FSControl
» OS_FSControl 28
OS_ FSControl 28
(SWI &29)
| Entry | |
|---|---|
| R0 | 28 (&1C) |
| R1 | Pointer to wildcarded filename of files to count |
| R3 | Flags |
| R4 | Start load |
| R5 | Start exec |
| R6 | End load |
| R7 | End exec |
| R8 | Pointer to descriptor |
| Exit | |
|---|---|
| R2 | Total length |
| R3 | Number of files |
| All registers preserved | |
Use
The purpose of this call is to count objects. It is equivalent to the *Count command.
Notes
The descriptor block, introduced in FileSwitch 2.73, should be used when counting discs larger than 4 Gbytes since the register R2 alone cannot return more than this. If the descriptor block is not used and the result overflowed R2 the value 0×7FFFFFFF is substituted (prior to this change the count total modulo 4 Gbytes was returned).
See also
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