Memory Information

GlobalMemoryStatusEx

The GlobalMemoryStatusEx function retrieves information about the current system's memory usage, including available and total memory. This function is useful for applications that need to monitor or adapt to memory conditions.

Syntax

BOOL GlobalMemoryStatusEx(
  LPMEMORYSTATUSEX lpBuffer
);
            

Parameters

Return Value

If the function succeeds, the return value is non-zero. If the function fails, the return value is zero. To get extended error information, call GetLastError.

Remarks

The MEMORYSTATUSEX structure provides a snapshot of memory utilization. The values it returns can change rapidly, so they might not be accurate by the time the application uses them. For most applications, the precise details of memory usage are not critical; it is generally sufficient to know if memory is available.

The dwLength member of the MEMORYSTATUSEX structure must be set before calling this function.

MEMORYSTATUSEX Structure

Member	Description
dwLength	Specifies the size of the structure, in bytes. This member must be set to sizeof(MEMORYSTATUSEX).
dwMemoryLoad	A number between 0 and 100 that specifies the approximate percentage of physical memory that is in use.
ullTotalPhys	The total size of physical memory, in bytes.
ullAvailPhys	The available physical memory, in bytes.
ullTotalPageFile	The total size of the virtual memory paging file, in bytes.
ullAvailPageFile	The available virtual memory for the paging file, in bytes.
ullTotalVirtual	The size of the user-mode portion of the virtual address space of the calling process, in bytes. This member is not used.
ullAvailVirtual	The available extended portion of the virtual address space of the calling process, in bytes. This member is not used.
Processes in Use	This field is deprecated and reserved.
Processes Available	This field is deprecated and reserved.

Example

#include <windows.h>
#include <iostream>

int main() {
    MEMORYSTATUSEX memInfo;
    memInfo.dwLength = sizeof(MEMORYSTATUSEX);

    if (GlobalMemoryStatusEx(&memInfo)) {
        std::cout << "Percentage of memory in use: " << (int)memInfo.dwMemoryLoad << "%" << std::endl;
        std::cout << "Total physical memory: " << memInfo.ullTotalPhys / (1024 * 1024) << " MB" << std::endl;
        std::cout << "Available physical memory: " << memInfo.ullAvailPhys / (1024 * 1024) << " MB" << std::endl;
        std::cout << "Total page file: " << memInfo.ullTotalPageFile / (1024 * 1024) << " MB" << std::endl;
        std::cout << "Available page file: " << memInfo.ullAvailPageFile / (1024 * 1024) << " MB" << std::endl;
    } else {
        std::cerr << "Failed to get memory status. Error code: " << GetLastError() << std::endl;
    }

    return 0;
}