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58 lines
1.8 KiB
Markdown
58 lines
1.8 KiB
Markdown
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The [_MEMNEW](_MEMNEW) function allocates new memory and returns a [_MEM](_MEM) memory block referring to it.
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## Syntax
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> memoryBlock = [_MEMNEW](_MEMNEW)(byteSize)
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## Parameter(s)
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* The byteSize parameter is the desired byte size of the memory block based on the variable [Variable Types](Variable-Types) it will hold.
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## Description
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* The memoryBlock value created holds the elements .OFFSET, .SIZE, .TYPE and .ELEMENTSIZE.
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* [_MEMNEW](_MEMNEW) does not clear the data previously in the memory block it allocates, for speed purposes.
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* To clear previous data from a new memory block, use [_MEMFILL](_MEMFILL) with a byte value of 0.
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* When a new memory block is created the memory .TYPE value will be 0.
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* **If the read only memory block .SIZE is 0, the memory block was not created.**
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* **All values created by memory functions must be freed using [_MEMFREE](_MEMFREE) with a valid [_MEM](_MEM) variable.**
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## Example(s)
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Shows how [SINGLE](SINGLE) numerical values can be passed, but non-fixed [STRING](STRING) lengths cannot get the value.
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```vb
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DIM m AS _MEM
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DIM f AS STRING * 5
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m = _MEMNEW(5) 'create new memory block of 5 bytes
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a = 12345.6
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_MEMPUT m, m.OFFSET, a 'put single value
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_MEMGET m, m.OFFSET, b 'get single value
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PRINT "b = "; b
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c$ = "Doggy"
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_MEMPUT m, m.OFFSET, c$ 'put 5 byte string value
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_MEMGET m, m.OFFSET, d$ 'get unfixed length string value
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_MEMGET m, m.OFFSET, f 'get 5 byte string value
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e$ = _MEMGET(m, m.OFFSET, STRING * 5) 'get 5 byte string value
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PRINT "d$ = "; d$; LEN(d$) 'prints empty string
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PRINT "e$ = "; e$; LEN(e$)
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PRINT "f = "; f; LEN(f)
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```
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```text
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b = 12345.6
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d$ = 0
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e$ = Doggy 5
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f = Doggy 5
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```
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## See Also
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* [_MEM](_MEM), [_MEMPUT](_MEMPUT)
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* [_MEMGET](_MEMGET), [_MEMGET (function)](_MEMGET-(function))
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* [_MEMFILL](_MEMFILL), [_MEMFREE](_MEMFREE)
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