HelpPC 2.10	Quick Reference Utility	Copyright 1991 David Jurgens
BCB - Batch Control Block (undocumented)                        DOS 2.x thru DOS 3.2  BCB Format     Offset Size                   Description        00   byte       unknown        01   word       if non-zero; segment of control block for active FOR        03   byte       type of batch command                            0 - normal batch command                            1 - FOR-loop active        04   dword      offset of next command to execute in batch file        07   word       offset of variable %0 (batch file name)        09  9 words     offset of %N batch file parameters, 0FFFFh indicates                        parameter is null        1C   nbytes     null terminated path and filename of the current                        batch file immediately followed by command line                        parameters.  Each parameter %0-%9 plus a CR is                        appended and resulting string is null terminated.                              DOS 3.3  BCB Format     Offset Size                   Description        00   byte       unknown        01   byte       global echo switch, if exec'd by batch CALL-command                            1 - turn ECHO ON on return to calling batch file                            0 - turn ECHO OFF on return to calling batch file        02   word       batch file BCD segment if executed via CALL                            if zero; batch file was called from command line                            if non-zero; batch file executed via CALL-command        04   word       if non-zero; segment of control block for active FOR        06   byte       type of batch command                            0 - normal batch command                            1 - FOR-loop active        07   dword      offset of next command to execute in batch file        0B   word       offset of variable %0 (batch file name)        0D  9words      offset of %N batch file parameters, 0FFFFh indicates                        parameter is null        1F  nbytes      null terminated path and filename of the current                        batch file immediately followed by command line                        parameters.  Each parameter %0-%9 plus a CR is                        appended and resulting string is null terminated.        - BCB length is variable and depends on the size and count of the          parameters and fully qualified batch file name        - the MCB for a BCB has a process Id of the transient portion of          the latest COMMAND.COM        - offsets displayed are relative to the BCB segment        - SHIFT command changes the offsets of the parameters in the table          at the offsets 0B0h thru 1Ch        - BCB  of DOS 3.3 is the  same as earlier versions except 3 bytes          were added after offset 0        - to find a BCB, locate the first block in the MCB chain belonging          to COMMAND.COM (the second allocated block always belongs to          COMMAND.COM).  Then scan the MCB chain for a 64 byte block with          the same owner ID as COMMAND.COM).  This will be the BCB.
Esc or Alt-X to exit	Batch Control Block	Home/PgUp/PgDn/End ←↑↓→