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C++: Set name of the thread

Did you know that you can set an arbitrary name for a thread and make it visible to the debugger?

For example, when debugging with JetBrains CLion, the thread name is visible in the threads dropdown.

debug.png

This is how it’s done:

#if defined(__APPLE__)
#include <pthread.h>
#endif
#if defined(__linux__)
#include <sys/prctl.h>
#endif
#ifdef _WIN32
#include <windows.h>
typedef HRESULT(WINAPI* pfnSetThreadDescription)(HANDLE, PCWSTR);
#endif

void setThreadName(const char* name) {
#if defined(_WIN32)
    (void)name;
    wchar_t wname[256];
    if (MultiByteToWideChar(CP_UTF8, MB_ERR_INVALID_CHARS, name, -1, wname, 256) > 0) {
        HMODULE kernel32 = GetModuleHandleW(L"kernel32.dll");
        if (kernel32) {
            pfnSetThreadDescription pSetThreadDescription =
                (pfnSetThreadDescription)GetProcAddress(kernel32, "SetThreadDescription");
            if (pSetThreadDescription) {
                pSetThreadDescription(GetCurrentThread(), wname);
            }
        }
    }
#elif defined(__APPLE__)
    pthread_setname_np(name);
#elif defined(__linux__)
    prctl(PR_SET_NAME, name);
#endif
}