The ACM driver stream I/O functions are called in the following circumstances:
| Function: | Called: |
|---|---|
| ACM_Init | By the Device Manager, when the driver is loaded |
| ACM_Deinit | By the Device Manager, when the driver is unloaded |
| ACM_Open | By the Wave API Manager, when the driver is opened for use. |
| ACM_Close | By the Wave API Manager, when the driver is done being used. |
| ACM_Read | Never |
| ACM_Write | Never |
| ACM_Seek | Never |
| ACM_PowerUp | By the Device Manager, when the system resumes from the suspend state. |
| ACM_PowerDown | By the Device Manager, when the system enters the suspend state. |
| ACM_IOControl | By the Wave API Manager to pass messages to and receive information from the driver. |
For more information about these functions, see ACM Driver Functions.