ÁDDITIONAL ÈELP ON ÃÓ-ÄÏÓ ÂATCH ÆILES
ÔHINGS THE DOCS DON'T TELL YA'
2/14/93
ÒANDY ×INCHESTER
 
ÈERE ARE A FEW POINTERS AND SUGGESTIONS ABOUT CONSTRUCTING ÃÓ-ÄÏÓ BATCH
FILES THAT WERE LEARNED THE HARD WAY.  ÍANY OF THEM WEREN'T OBVIOUS FROM
READING ÃÓ-ÄÏÓ DOCUMENTATION.  ÓOME ARE PROBABLY JUST QUIRKY LITTLE THINGS
THAT EVEN ÃHRIS ÓMEETS DIDN'T EVEN KNOW ABOUT ANYWAY.  É'LL BASICALLY JUST
PICK APART SOME COMMANDS FROM A FEW OF THE BATCH FILES IN THIS COLLECTION.
 
ÆIRST, HERE'S THE BATCH FILE ÃÄ (BECAUSE IT'S SHORT) WITH A FEW ADDED
COMENTS:
 
PUSHDIR
 
  ÔHIS SAVES THE LOGGED DRIVE.  ÏTHER DRIVES CAN THEN BE LOGGED BY THE
  BATCH FILE, AND THE ORIGINAL LOGGED DRIVE RESTORED WITH POPDIR.
 
IF "%1"=" "GOTO NOARG
 
  %1 REFERS TO THE FIRST PARAMETER OF THE COMMAND TAIL.  ÉF THERE IS NO
  COMMAND TAIL, A SPACE IS RETURNED, NOT A NULL STRING.
 
X$="%1"
 
  ÃOMMAND TAIL PARAMETERS CAN BE ASSIGNED TO OTHER STRINGS, X$ IN THIS
  CASE.  ÁNY TIME A COMMAND PARAMETER IS COMPARED TO A STRING OR ASSIGNED
  TO A VARIABLE, IT MUST BE SURROUNDED BY DOUBLE QUOTES.
 
IF MID$(X$,2,1)=":"THEN A=ASC(X$):SYS5888,A:X$=MID$(X$,3,LEN(X$)-2)
 
  ÔHIS LINE IS PURE ÂÁÓÉÃ 7.0.  ÉT LOOKS AT X$ TO SEE IF THE SECOND
  CHARACTER IS A COLON.  ÉF SO, THE FIRST CHARACTER MUST BE A DRIVE LETTER.
  ÔHE ÃÓ-ÄÏÓ ROUTINE AT 5888 TAKES THE ÁÓÃÉÉ VALUE OF THE CHARACTER IN THE
  VARIABLE "A" AND LOGS IT AS THE NEW DRIVE.  ÔHE REMAINDER OF THE LINE
  STRIPS FIRST TWO CHARACTERS FROM X$.
 
POKE7136,0:IF X$="/"THEN POKE7136,1
IF ERRORLEVEL 1 GOTO ROOT
 
  ÔHIS LITTLE SUBTERFUGE IS NECESSARY BECAUSE ÃÓ-ÄÏÓ AND ÂÁÓÉÃ COMMANDS
  DON'T MIX WELL.  ÉT CHECKS X$ TO SEE IF IT IS EQUAL TO THE "/" CHARACTER
  USED FOR SPECIFYING THE ROOT DIRECTORY.  ÕNFORTUNATELY, A LINE LIKE:
       IF X$="/" GOTO ROOT
  DOESN'T WORK.  ÔO GET AROUND THIS, THE ÃÓ-ÄÏÓ ERRORLEVEL IS CLEARED BY
  POKING IT WITH A 0.  ÔHEN IF X$="/" SET ERRORLEVEL TO ONE BY POKING IT
  WITH 1.  (ÅRRORLEVEL IS LOCATED AT 7136).  ÔHE SECOND LINE CHECKS
  ERRORLEVEL, AND GOES TO THE LABLE ROOT IF X$ WAS EQUAL TO "/".
 
>/%1
GOTO DONE
 
  ÔHIS USES THE ÃÓ-ÄÏÓ SHELL'S WEDGE TO OPEN THE SUBDIRECTORY NAMED IN THE
  COMMAND TAIL.  ÙOU HAVE TO BE ESPECIALLY CAREFUL USING THE WEDGE ">"
  CHARACTER IN A BATCH FILE BECAUSE UNLESS IT IS THE FIRST CHARACTER ON A
  LINE, IT CAN BE MISTAKEN FOR THE OUTPUT REDIRECTION ">" CHARACTER.
 
:ROOT
>/
GOTO DONE
 
  ÌABELS ARE ALWAYS PRECEEDED BY A ":" AND MUST START IN THE FIRST COLUMN
  OF THE LINE.  ÉF A LABEL IS PRECEEDED BY A SPACE OR OTHER CHARACTER, IT
  WON'T BE FOUND.
 
:NOARG
ECHO ÓYNTAX: %0 [D:] DIRECTORY
 
  ÔHE %0 PARAMETER ECHOS THE NAME OF THE COMMAND ITSSELF, IN THIS CASE, CD.
  ÉF THE NAME OF THE COMMAND IS CHANGED, THAT IS, IF CD IS RENAMED, THE NEW
  WILL SHOW UP ON THE ÓYNTAX SUMMARY.
 
:DONE
POPDIR
 
  ÐOPDIR RESTORES THE DRIVE THAT WAS LOGGED WHEN THE BATCH FILE WAS RUN.
 
  ÔHE FOLLOWING TIDBIT IS THE ENTIRE STRING SEARCH ROUTINE FROM THE DEX
  BATCH FILE:
 
IF EXIST DEX.TXT GREP -Y %1 DEX.TXT
IF EXIST DEX.TXT GOTO DONE
SYS5888,90
IF EXIST DEX.TXT GREP -Y %1 DEX.TXT
IF NOT EXIST DEX.TXT GOTO NOTFOUND
GOTO DONE
 
  ÉF THE FILE ÄÅØ.ÔØÔ IS PRESENT ON THE LOGGED DRIVE, THEN ÇÒÅÐ IS USED TO
  TO SEARCH FOR THE STRING THAT WAS GIVEN ON THE COMMAND LINE.  ÉF ÄÅØ.ÔØÔ
  WASN'T FOUND, THE ROUTINE FALLS THROUGH TO SYS5888,90 TO LOG THE BOOT
  DRIVE (DRIVE Z), AND TRY AGAIN.  ÉF ÄÅØ.ÔØÔ STILL ISN'T FOUND, CODE AFTER
  THE LABEL "NOTFOUND" LETS THE USER KNOW THAT THE FILE ISN'T THERE.
 
  ÔHE NEXT THREE LINES APPEAR IN THE BATCH FILE ÍÁÎ:
 
ECHO "“ ÍANUAL FOR "%1" "
?CHR$(27)"T"
CHAR0,0,20,"",0
 
  ÙOU CAN INCLUDE CONTROL CHARACTERS SUCH AS ÈÏÍÅ, ÃÌÒ, ÓWITCH TO ÌOWER
  ÃASE, AND ÒVS ÏN, WITH THE ECHO COMMAND IF YOU PRECEED THEM WITH A
  A DOUBLE QUOTE.  ÃOMPLEX SCREEN FORMATTING IS POSSIBLE BY PRINTING ÅÓÃ
  SEQUENCES FOR WINDOWING, AND POSITIONING THE CURSOR WITH THE ÃÈÁÒ
  COMMAND.
 
LHX -P %1.LZH"
 
  ÔHIS WAS JUST PLAIN QUIRKY!  ÔHE ÌÈØ COMMAND COULDN'T SUCCESSFULLY DO
  THE REQUESTED PATTERN MATCHING WHEN INCLUDED IN A BATCH FILE UNLESS IT
  FOLLOWED BY A DOUBLE QUOTE.  É DON'T REMEMBER HOW É FINALLY FIGURED THAT
  OUT, BUT IT WOULDN'T WORK ANY OTHER WAY.