47 lines
907 B
Markdown
47 lines
907 B
Markdown
# PR_MemMap
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Maps a section of a file to memory.
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## Syntax
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```{code}
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#include <prio.h>
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void* PR_MemMap(
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PRFileMap *fmap,
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PRInt64 offset,
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PRUint32 len);
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```
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### Parameters
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The function has the following parameters:
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`fmap`
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: A pointer to the file-mapping object representing the file to be
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memory-mapped.
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`offset`
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: The starting offset of the section of file to be mapped. The offset
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must be aligned to whole pages.
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`len`
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: Length of the section of the file to be mapped.
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### Returns
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The starting address of the memory region to which the section of file
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is mapped. Returns `NULL` on error.
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## Description
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{ref}`PR_MemMap` maps a section of the file represented by the file mapping
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`fmap` to memory. The section of the file starts at `offset` and has
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the length `len`.
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When the file-mapping memory region is no longer needed, it should be
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unmapped with a call to {ref}`PR_MemUnmap`.
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