@ZERO,HELP
ZERO 1R2B - Write zeroes or any word to specified area of a file

CALL: @ZERO[,options] Filename.,[Start.]Count|-End[/Word-to-store]

  Filename - Qualified filename or internal name (no period needed).
  Start - File address where writing starts. Start or Count octal if leading 0.
  Count|-End - Amount to write; or address where writing ends, preceded by -.
  Word-to-store - Octal word to write to file instead of 0. Use negative of
                  word by preceding with - (if < 12 digits) or using N option.
Precede Start/Count/-End with S-sectors, T-tracks, P-positions, or W-words;
        default=tracks. Units for Start apply to Count|-End unless specified.
Count: T5.10 (Track 5 for 10 tracks); End: S13.-S29 (Sector 13 to Sector 29)
Options: A - Zero all of file. (Same as M with no Start parameter)
         H - Zero to highest granule written.  HELP - Display these lines.
         I - Zero initial reserve. If both H & I, use the higher of the two.
         L - Zero last track or word of max granule (init. resv. if I opt.)
         M - Zero to maximum granules. (H, I, & M can have Start parameter.)
         N - Use negative of store word (or precede with '-' if < 12 digits).
         R - Release rather than zero specified area. RZ - Zero and release.
         S - Snap words 4 & 5 of each I/O (minus 'N' bit)

   EXAMPLES: @ZERO  BRKPT-FILE.,1000/770000000000     @ZERO,N MYTEST,S5.S20