Managing Files In The Host OS

The following file management operations can be performed using the Parallels C API on the host machine:

• Obtaining a directory listing.
• Creating directories.
• Automatically generate unique names for new file system entries.
• Rename file system entries.
• Delete file system entries.

The file management functionality can be accessed through the PHT_SERVER handle. The file management functions are prefixed with "PrlSrv_Fs".

Obtaining the host OS directory listing

The directory listing is obtained using the PrlSrv_FsGetDirEntries function. The function returns a handle of type PHT_REMOTE_FILESYSTEM_INFO containing the information about the specified file system entry and its immediate child entries (if any). The child entries are returned as a list of handles of type PHT_REMOTE_FILESYSTEM_ENTRY which is included in the PHT_REMOTE_FILESYSTEM_INFO object. The sample function below demonstrates how to obtain a listing for the specified directory. On initial call, the function obtains a list of child entries (files and sub-directories) for the specified directory and is then called recursively for each file system entry returned. On completion, the entire directory tree will be displayed on the screen.

// Obtains the entire directory tree in the host OS

// starting at the specified path.

// The "levels" parameter specifies how many levels should the

// function traverse down the directory tree.

PRL_RESULT GetHostDirList(PRL_HANDLE hServer, PRL_CONST_STR path, int levels)

{

PRL_HANDLE hJob = PRL_INVALID_HANDLE;

PRL_HANDLE hJobResult = PRL_INVALID_HANDLE;

PRL_HANDLE hParentDirectory = PRL_INVALID_HANDLE;

PRL_HANDLE hChildElement = PRL_INVALID_HANDLE;

PRL_RESULT ret = PRL_ERR_UNINITIALIZED;

PRL_RESULT nJobReturnCode = PRL_ERR_UNINITIALIZED;

// Get directory list from the host.

// The second parameter specifies the absolute

// path for which to get the directory listing.

hJob = PrlSrv_FsGetDirEntries(hServer, path);

// Wait for the job to complete.

ret = PrlJob_Wait(hJob, 1000);

if (PRL_FAILED(ret))

{

// Handle the error...

return -1;

}

// Analyze the result of PrlSrv_FsGetDirEntries.

ret = PrlJob_GetRetCode(hJob, &nJobReturnCode);

if (PRL_FAILED(ret))

{

// Handle the error...

PrlHandle_Free(hJob);

return -1;

}

// Check the job return code.

if (PRL_FAILED(nJobReturnCode))

{

// Handle the error...

PrlHandle_Free(hJob);

return -1;

}

// Get job result.

ret = PrlJob_GetResult(hJob, &hJobResult);

PrlHandle_Free(hJob);

if (PRL_FAILED(ret))

{

// Handle the error...

return -1;

}

// Get a handle to the parent directory.

// This is the directory that we specified in the

// PrlSrv_FsGetDirEntries call above.

ret = PrlResult_GetParam(hJobResult, &hParentDirectory);

PrlHandle_Free(hJobResult);

if (PRL_FAILED(ret))

{

// Handle the error...

return -1;

}

// Get parameter count (the number of child entries).

PRL_UINT32 nParamCount = 0;

ret = PrlFsInfo_GetChildEntriesCount(hParentDirectory, &nParamCount);

if (PRL_FAILED(ret))

{

// Handle the error...

PrlHandle_Free(hJob);

return -1;

}

// Iterate through the list obtaining

// a handle of type PHT_REMOTE_FILESYSTEM_ENTRY

// for each child element of the parent directory.

for (PRL_UINT32 i = 0; i < nParamCount; ++i)

{

// Get a handle to the child element.

ret = PrlFsInfo_GetChildEntry(hParentDirectory, i, &hChildElement);

if (PRL_FAILED(ret))

{

// Handle the error...

continue;

}

// Get the filesystem element name.

PRL_CHAR sBuf[1024];

PRL_UINT32 nBufSize = sizeof(sBuf);

ret = PrlFsEntry_GetAbsolutePath(hChildElement, sBuf, &nBufSize);

if (PRL_FAILED(ret))

{

// Handle the error...

PrlHandle_Free(hChildElement);

continue;

}

printf("%s\n", sBuf);

PrlHandle_Free(hChildElement);

// Recursive call. Obtains directory listing for

// the entry returned in this iteration.

if (levels > 0 || levels <= -1)

{

int count = levels - 1;

GetHostDirList(hServer, sBuf, count);

}

}

PrlHandle_Free(hParentDirectory);

PrlHandle_Free(hJob);

return PRL_ERR_SUCCESS;

}