- 1 year ago
CreateToolhelp32Snapshot(TH32CS_SNAPMODULE | TH32CS_SNAPMODULE32, PID) returns INVALID_HANDLE_VALUE
When CreateToolhelp32Snapshot
returns INVALID_HANDLE_VALUE
(or -1
), it indicates that the snapshot creation failed. There could be several reasons for this. Here are a few troubleshooting steps you can follow:
Ensure proper privileges: Make sure that your process has the necessary privileges to create a snapshot. If your process does not have sufficient privileges, the snapshot creation may fail. Try running your code with elevated privileges or as an administrator.
Check error code: Retrieve the error code using
GetLastError
after theCreateToolhelp32Snapshot
call fails. This will provide more information about the specific reason for the failure. You can useFormatMessage
to retrieve a human-readable error message based on the error code.Verify snapshot flags: Double-check the snapshot flags passed to the
CreateToolhelp32Snapshot
function. Ensure that you have provided the correct flags based on your specific requirements. For example, if you are capturing module information, the flagsTH32CS_SNAPMODULE
andTH32CS_SNAPMODULE32
should be used.Validate process ID: Ensure that the process ID (
PID
) passed to theCreateToolhelp32Snapshot
function is valid. Make sure that the process with the specified ID exists and is running. You can use other functions likeProcess32First
orProcess32Next
to iterate through the running processes and verify the process ID.Handle 32-bit vs. 64-bit compatibility: If you are running a 32-bit application on a 64-bit system, ensure that you are using the appropriate flags and handling the differences between 32-bit and 64-bit processes.
By following these steps, you can identify the cause of the failure in creating the snapshot using CreateToolhelp32Snapshot
and take appropriate measures to address the issue.