In a single command block, commands can be assembled to form a logical unit. The block is introduced by a BEGIN-BLOCK command and terminated by an END-BLOCK command. Between these two commands are the commands which are to be executed in the block. Single command blocks are also referred to as BEGIN blocks.
The command line of the BEGIN-BLOCK command can begin with a tag, in accordance with the rules for S tags. This tag directly links the END-BLOCK command to the BEGIN-BLOCK command; it can also be used by other commands, as a branch destination.
If the BEGIN-BLOCK command line contains no tag, the implicit assignment between BEGIN-BLOCK and END-BLOCK commands takes effect: i.e. the END-BLOCK command always refers implicitly to the last BEGIN-BLOCK command that has not yet been terminated by END-BLOCK.
Layout of a BEGIN block without a tag
/BEGIN-BLOCK [command sequence] /END-BLOCK
Layout of a BEGIN block with a tag
/tag: BEGIN-BLOCK [command sequence] /END-BLOCK [BLOCK = tag]