User Interface

The WDFS provides two sets of interface for file access. The first is a standard C interface to the file system:

• fopen
• fclose
• fdopen
• fseek
• fread
• fwrite
• fscanf
• ftell
• ferror
• feof
• frewind

The syntax of these functions has been kept to be the same as in the C library where possible. The few exceptions were:

• fopen only "r" "w" "r+" "w+" types are supported. The "b" option can also be used, mainly for compatibility reason, since WDFS treats them the same.
• fdopen null function

Manual pages for all of these functions exist and should be referenced in the first instance.

The second set of user interfaces is Unix system call like and this provides a more direct and efficient interface to the underlying RPC mechanism.

• open
• close
• lseek
• read
• write

It maps almost directly onto the MSRPC calls and therefore has the same size limit on the data unit that MSRPC has. The maximum data length should be less than (1500 - 2 - PUID_size - QOS_param - 8). Note that this interface has been integrated with the Wanda Unix Compatible library to allow uniform access to the file system and Wanda socket library. Furthermore, this interface has been carefully coded to have no dependency on the stdio code which exists only in the user space. This makes Wanda kernel WDFS integration is a trivial task.