 
 BCK copies standard RMS-11 files from one medium to another
 (disk to disk or disk to tape), translating the data into a
 special back-up format.  The back-up copy contains the source
 file's attributes:  account number, creation and revision dates,
 protection code, and so on.  However, they do not include
 placement control instructions; a file cannot be restored to
 the same physical place on a device that it was backed up
 from.
 
 Back-up files can only be accessed properly by the RST utility
 (type HELP RMS RST for more information).  User programs cannot
 change back-up data.
 
 BCK only uses magnetic tapes with ANSI-standard labels.  However,
 the back-up data written by the utility between the labels does
 not comply with ANSI standards.
 
 Type HELP RMS BCK COMMAND for an explanation of BCK's command line
 and switches.
 
*COMMAND
 
 The general BCK command line is:
 
        outfile[/switch(s)]=infile[/switch(s)][,infile[/switch(s)] ...]
 
*SWITCHES
 Switch         Type       Description                  Default
 
 ?              string     Print HELP message           No help

 /ID            Global     Identify current version     No id
                           of BCK
 
 /QU            Global     Enable Query mode            QU
 
 /SL[:file]     Global     Provide summary listing (in  No summary
                           file, if specified)
 
 /RA            Outfile    Read after writing           NORA
 
 /RC            Outfile    Check after writing          NORC
 
 /RW            Outfile    Rewind magtape before        NORW
                           writing
 
 /SU            Outfile    Supercede old files          NOSU
 
 /CD:date[:v]   Infile     Back-up files based on       No date checking
                           creation date
 
 /RD:date[:v]   Infile     Back-up files based on       No date checking
                           revision date
 
 where  date = dd-mon-yy
        v    = None, created/revised on the specified date
               A, created/revised after the specified date
               B, created/revised after the specified date
