Process ID Functions (Windows Embedded CE 6.0)
1/6/2010
There are several process ID functions in Windows Embedded CE 6.0. This topic covers each one of these in detail. New functions added in CE 6.0 are marked as such. The following table describes these functions.
| Function | Description |
|---|---|
This is a pseudo handle value which is always a constant value used to refer to the currently active process in which context the calling thread is running. This function is the same as previous versions of Windows Embedded CE. |
|
This is the ID of the process in which context the calling thread is running. If the calling thread is not in a PSL or in an API call, this process ID should be same as the current thread owner process ID. This function is the same as previous versions of Windows Embedded CE. |
|
From user mode. This is the ID of the process that made the call to the current context of the calling thread. This always excludes kernel from the callstack chain. |
|
New. From kernel mode. This is the ID of the process that made the call to the current context of the calling thread. Functionality is the same as GetDirectCallerProcessId. |
|
New. From user mode. This is the ID of the process that made the call to the current context of the calling thread. The main difference between this function and GetCallerProcess comes when the caller is the same as the owner process of the calling thread. |
|
New. From kernel mode. If the direct call bit is set, this function reterns the kernel process ID. If the direct call bit is not set, this function returns the process ID of the currently active virtual memory (VM). |
|
New. From user mode. If the direct call bit is set, this function reterns the kernel process ID. If the direct call bit is not set, this function returns the process ID of the currently active VM. Functionality is the same as GetDirectCallerProcessId. |
|
New. From kernel mode. This is the ID of the process whose VM is currently active. |
Process ID
The following table compares these functions in different situations.
Scenario |
GetCallerProcess |
GetDirectCallerProcessID |
GetCallerVMProcessID |
1 |
NULL |
User A |
User A |
2 |
Kernel |
Kernel |
Kernel |
3 |
Kernel |
Kernel |
Kernel |
4 |
Active VM process |
Active VM process |
Active VM process |
5 |
User B |
User B |
User B |
6a |
Kernel |
Kernel |
Active VM process |
6b |
Active VM process |
Active VM process |
Active VM process |
7 |
User A |
User A |
User A |
8 |
Active VM process |
Active VM process |
Active VM process |
The following are the scenario descriptions:
1. User-mode thread with no outgoing calls to any other process.
2. Kernel-mode thread with no outgoing calls to any other process.
3. Kernel-mode thread calling into a user-mode PSL/driver.
4. User-mode thread calling into kernel PSL/driver.
5. Kernel-mode thread calling into a user-mode PSL/driver, which in turn calls another user-mode PSL/driver.
6a. User-mode thread calling into a kernel PSL/driver, which in turn calls another kernel PSL/driver with the direct call bit set.
6b. User-mode thread calling into a kernel PSL/driver, which in turn calls another kernel PSL/driver with the direct call bit not set.
7. User-mode thread calling into another user-mode PSL/driver through the kernel. This scenario is same as 5.
8. Kernel-mode thread calling into a user-mode PSL, which in turn calls a kernel-mode PSL/driver. This scenario is same as 4.