Hprocess

hProcess is a handle to a process object in the Windows API. It is an opaque value returned by functions such as CreateProcess and OpenProcess and is stored in the calling process’s handle table. The handle serves as a reference to the newly created or existing process object and is used with various API calls to monitor or control the process.

Common uses of hProcess include waiting for a process to finish, querying its exit code, and terminating or altering its priority. For example, WaitForSingleObject(hProcess, ...) can pause the calling thread until the process ends, GetExitCodeProcess retrieves the process’s termination status, and TerminateProcess can forcibly stop it. Other functions may query or modify process attributes, such as GetPriorityClass or SetPriorityClass. It is important to CloseHandle when the handle is no longer needed to release system resources.

Lifetime and rights: a process handle remains valid until it is closed with CloseHandle. The access rights associated with the handle depend on how it was opened or created; common rights include PROCESS_QUERY_INFORMATION, PROCESS_VM_READ, or PROCESS_TERMINATE. If a handle is marked as inheritable and the creating process uses a process creation flag that allows handle inheritance, a copy of the handle may be inherited by a newly created child process.

Important distinctions: hProcess is a handle, not a process ID (PID). The PID can be retrieved from a process handle via GetProcessId if needed. Handles are valid within the owning process and, with duplication or explicit inheritance, can be shared with other processes. In practice, hProcess is the primary means of programmatically interacting with and managing Windows process objects.