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40 lines
895 B
Nim
40 lines
895 B
Nim
discard """
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disabled: "Windows"
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output: '''Full read size: 20
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Half read size: 10 Data: Hello'''
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"""
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import memfiles, os
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const
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fn = "test.mmap"
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var
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mm, mm_full, mm_half: MemFile
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p: pointer
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if fileExists(fn): removeFile(fn)
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# Create a new file, data all zeros
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mm = memfiles.open(fn, mode = fmReadWrite, newFileSize = 20)
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mm.close()
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# read, change
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mm_full = memfiles.open(fn, mode = fmWrite, mappedSize = -1, allowRemap = true)
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let size = mm_full.size
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p = mm_full.mapMem(fmReadWrite, 20, 0)
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echo "Full read size: ", size
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var p2 = cast[cstring](p)
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p2[0] = 'H'
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p2[1] = 'e'
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p2[2] = 'l'
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p2[3] = 'l'
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p2[4] = 'o'
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p2[5] = '\0'
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mm_full.unmapMem(p, 20)
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mm_full.close()
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# read half, and verify data change
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mm_half = memfiles.open(fn, mode = fmRead, mappedSize = 10)
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echo "Half read size: ", mm_half.size, " Data: ", cast[cstring](mm_half.mem)
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mm_half.close()
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if fileExists(fn): removeFile(fn)
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