Added PXENV_GET_FILE_SIZE.

Documented non-blocking nature of PXENV_FILE_READ.

Changed FileName field in PXENV_FILE_OPEN to be a SEGOFF16, to avoid a
fixed 256-byte length limit on URLs.

diff --git a/src/doc/pxe_extensions b/src/doc/pxe_extensions
index ae03b39..0d04fcd 100644 (file)
--- a/src/doc/pxe_extensions
+++ b/src/doc/pxe_extensions
@@ -17,8 +17,8 @@ Description:  Opens a file specified by a URL for reading.  Multiple
 typedef struct s_PXENV_FILE_OPEN {
        PXENV_STATUS Status;
        UINT16 FileHandle;
+       SEGOFF16 FileName;
        UINT32 Reserved;
-       UINT8 FileName[256];
 } t_PXENV_FILE_OPEN;
 
 
@@ -122,6 +122,12 @@ Output:            PXENV_EXIT_SUCCESS or PXENV_EXIT_FAILURE must be
                structure must be set to one of the values represented
                by the PXENV_STATUS_xxx constants.
 
+               This API function is non-blocking.  PXENV_EXIT_SUCCESS
+               and PXENV_STATUS_SUCCESS is returned if a data block
+               has been transferred into the caller's buffer.
+               PXENV_EXIT_FAILURE and PXENV_STATUS_FAILURE is
+               returned if no data is available to transfer.
+
 Description:   Read from a previously opened file.
 
 
@@ -149,3 +155,39 @@ BufferSize:        Number of bytes written to the data buffer.  End of
                file if this is zero.
 
 Status:                See PXENV_STATUS_xxx constants.
+
+
+
+
+GET FILE SIZE
+
+Op-Code:       PXENV_GET_FILE_SIZE (00e4h)
+
+Input:         Far pointer to a t_PXENV_GET_FILE_SIZE parameter
+               structure that has been initialised by the caller.
+
+Output:                PXENV_EXIT_SUCCESS or PXENV_EXIT_FAILURE must be
+               returned in AX.  The status field in the parameter
+               structure must be set to one of the values represented
+               by the PXENV_STATUS_xxx constants.
+
+Description:   Determine size of a previously opened file.
+
+
+typedef struct s_PXENV_GET_FILE_SIZE {
+       PXENV_STATUS Status;
+       UINT16 FileHandle;
+       UINT32 FileSize;
+} t_PXENV_GET_FILE_SIZE;
+
+
+Set before calling API service:
+
+FileHandle:    Handle obtained when file was opened.
+
+
+Returned from API service:
+
+FileSize:      Size of the file in bytes.
+
+Status:                See PXENV_STATUS_xxx constants.