Name

VixVM_ReadVariable

Description

VixHandle
VixVM_ReadVariable(VixHandle vmHandle,
                   int variableType,
                   const char *name,
                   int options,
                   VixEventProc *callbackProc,
                   void *clientData);

This function reads variables from the virtual machine state. This includes the virtual machine configuration, environment variables in the guest, and VMware "Guest Variables".

Parameters

vmHandle
Identifies a virtual machine. Call VixVM_Open() to create a virtual machine handle.
variableType
The type of variable to read. The currently supported values are:
name
The name of the variable.
options
must be 0.
callbackProc
A callback function that will be invoked when the operation is complete.
clientData
A parameter that will be passed to the callbackProc function.

Return Value

VixHandle. A job handle that describes the state of this asynchronous operation.

Remarks

Side Effects

None.

Requirements

vix.h, since Workstation 6.0

Example

This example writes and reads a variable you may define, called "myTestVariable".
VixError err = VIX_OK;
VixHandle hostHandle = VIX_INVALID_HANDLE;
VixHandle jobHandle = VIX_INVALID_HANDLE;
VixHandle vmHandle = VIX_INVALID_HANDLE;
char *readValue = NULL;

jobHandle = VixHost_Connect(VIX_API_VERSION,
                            VIX_SERVICEPROVIDER_VMWARE_WORKSTATION,
                            NULL, // hostName
                            0, // hostPort
                            NULL, // userName
                            NULL, // password
                            0, // options
                            VIX_INVALID_HANDLE, // propertyListHandle
                            NULL, // callbackProc
                            NULL); // clientData

err = VixJob_Wait(jobHandle,
                  VIX_PROPERTY_JOB_RESULT_HANDLE,
                  &hostHandle,
                  VIX_PROPERTY_NONE);

if (VIX_OK != err) {
   // Handle the error...
   goto abort;
}
Vix_ReleaseHandle(jobHandle);

jobHandle = VixVM_Open(hostHandle,
                       "c:\\Virtual Machines\\vm1\\win2000.vmx",
                       NULL, // callbackProc
                       NULL); // clientData
                       
err = VixJob_Wait(jobHandle,
                  VIX_PROPERTY_JOB_RESULT_HANDLE,
                  &vmHandle,
                  VIX_PROPERTY_NONE);
if (VIX_OK != err) {
   // Handle the error...
   goto abort;
}

Vix_ReleaseHandle(jobHandle);

// Power on the virtual machine before copying file.
jobHandle = VixVM_PowerOn(vmHandle,
                          0, // powerOnOptions
                          VIX_INVALID_HANDLE, // propertyListHandle
                          NULL, // callbackProc
                          NULL); // clientData

err = VixJob_Wait(jobHandle,VIX_PROPERTY_NONE);
if (VIX_OK != err) {
   // Handle the error...
   goto abort;
}

Vix_ReleaseHandle(jobHandle);

// Wait until guest is completely booted.
jobHandle = VixVM_WaitForToolsInGuest(vmHandle,
                                      300, // timeoutInSeconds
                                      NULL, // callbackProc
                                      NULL); // clientData

err = VixJob_Wait(jobHandle, VIX_PROPERTY_NONE);
if (VIX_OK != err) {
   // Handle the error...
   goto abort;
}

Vix_ReleaseHandle(jobHandle);
                               
jobHandle = VixVM_WriteVariable(vmHandle,
                                VIX_VM_GUEST_VARIABLE,
                                "myTestVariable",
                                "newValue",
                                0, // options
                                NULL, // callbackProc
                                NULL); // clientData);
err = VixJob_Wait(jobHandle, VIX_PROPERTY_NONE);
if (VIX_OK != err) {
   // Handle the error...
   goto abort;
}                              
                              
jobHandle = VixVM_ReadVariable(vmHandle,
                               VIX_VM_GUEST_VARIABLE,
                               "myTestVariable",
                               0, // options
                               NULL, // callbackProc
                               NULL); // clientData);
err = VixJob_Wait(jobHandle, 
                  VIX_PROPERTY_JOB_RESULT_VM_VARIABLE_STRING,
                  &readValue,
                  VIX_PROPERTY_NONE);
if (VIX_OK != err) {
   // Handle the error...
   goto abort;
}

abort:
Vix_FreeBuffer(readValue);
Vix_ReleaseHandle(jobHandle);
Vix_ReleaseHandle(vmHandle);
VixHost_Disconnect(hostHandle);

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