Topic       : TOS - The Operating System
Author      : 
Version     : tos.hyp (December 19, 2008)
Subject     : Programmieren/Atari
Nodes       : 3010
Index Size  : 93790
HCP-Version : 5
Compiled on : Atari
@charset    : atarist
@lang       : 
@default    : Title
@help       : 
@options    : +g -i -s +x +zz -t4
@width      : 70
View Ref-File13.13.2.5  Message group 2                                         TOS

ACC_META = 0x503
ACC_IMG  = 0x504

These message are used to exchange drawings and pictures. Only the 
file formats defined in the GEM documentation are used; they are 
sufficient to meet most requirements, and any GEM application should 
be able to handle them anyway.

  1. Sending a metafile:

          msg[0]:  ACC_META (0x503)
          msg[3]:  1 for the final part, 0 otherwise
          msg[4]:  and
          msg[5]:  Pointer to data
          msg[6]:  and
          msg[7]:  Length of data (32 bit longword)

     The metafile data is sent in the same format as it would be 
     stored on disk. As metafiles can become quite large, and often 
     accessories in particular do not have sufficient memory free to 
     store them, a file can be sent in several pieces. The receiver 
     has to take care of assembling all parts to restore the original 
     data, if neccessary by writing the parts to a file. The last part 
     of a file is marked by msg[3]=1. The sender may send no other 
     data between the parts of a file. msg[6] and msg[7] contain the 
     length of the part being sent, not the total length.

     The receiver acknowledges each part as described for @{"group 1" 
     LINK "Message group 1"}. As for text messages, the sender must 
     make sure that the data to be transferred is stored in globally 
     accessible memory.

  2. Sending a bit image file:

     msg[0]: ACC_IMG (0x504)

     otherwise identical to 1.