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4/8/2010

This function writes memory in a specified process. The entire area to be written to must be accessible, or the operation fails.

Syntax 

BOOL WriteProcessMemory(
  HANDLE 
hProcess,
  LPVOID 
lpBaseAddress,
  LPVOID 
lpBuffer,
  DWORD 
nSize,
  LPDWORD 
lpNumberOfBytesWritten
);

Parameters

hProcess

[in] Handle returned from the OpenProcessfunction that provided full access to the process.

lpBaseAddress

[in] Pointer to the base address in the specified process.

Before data transfer occurs, the system verifies that all data in the base address and memory of the specified size is accessible for write access. If so, the function proceeds; otherwise, the function fails.

lpBuffer

[in] Pointer to the buffer that supplies data to be written into the address space of the specified process.

nSize

[in] Specifies the requested number of bytes to write into the specified process.

lpNumberOfBytesWritten

[out] Pointer to the number of bytes transferred into the specified process.

This parameter is optional.

If lpNumberOfBytesWrittenis NULL, the parameter is ignored.

Return Value

Nonzero indicates success. Zero indicates failure. To get extended error information, call GetLastError.

The function fails if the requested write operation crosses into an area of the process that is inaccessible.

Remarks

WriteProcessMemorycopies data from the specified buffer in the current process to the address range of the specified process. The process whose address space is being written to is typically, but not necessarily, being debugged.

The entire area to be written to must be accessible. If it is not, the function fails.

Requirements

Header winbase.h
Library Nk.lib
Windows Embedded CE Windows CE 2.0 and later
Windows Mobile Windows Mobile Version 5.0 and later

See Also