Batch Commands

%0, %1, %2, %3, %4, %5, %6, %7, %8, %9 ... arguments to the batch file
 |
 %0 is the batch file itself

%variablename%  ... the name of the variable; the variable name is set by
                    the SET variablename=string command
                    Note the extra '%' at the end.

ECHO [ON|OFF|message]
  "echo blank" will produce a blank line on screen in DOS2.1
  "echo blank" will show ON/OFF on screen in DOS3.0
  "echo ASCII-255" to get a blank line in DOS3.1
  "echo." to get a blank line in DOS3.1
  @echo off   ... even the "echo off" will not be echoed (DOS 3.3)
  %@%echo off  ... good for various versions of DOS (set @=@ for DOS 3.3
                                                     set @=  for DOS 3.2)
CALL batchfile
  set call=call          for DOS 3.3
  set call=%comspec% /C  for DOS 3.2
  %call%                 ... usage that is good for various version of DOS

FOR %%variable IN (set) DO command  {set is a list of filename; * or ? can be
                                     used.}
  Note that two %% are used in a batch file, because one % is striped off when
  given to the command line; only one % is needed when given directly from the
  command line.}

GOTO label               {%1 etc. can also be used for label; see example below}

If [NOT] condition command
             |string1==string2         {upper & lower case letters matters}
             |EXIST [d:][path]filename {path in DOS3.0}
             |                         {path is not supported in DOS2.1}
             |ERRORLEVEL number        {true if the previous program exit
                                        with number or higher; See ask}

example of looping 7 times (i.e., 7 "-" signs)
  set count=
  :loop
  set count=%count%-
    command 1
    command 2
  if not "%count%"=="-------" %then% goto loop
  %else% set count=

example of looping 27 times (i.e., 2 "+" signs and 7 "-" signs)
  set count1=| set count2=   ... put two commands in one line with "|" redirection
  :loop
  set count1=%count1%-
    command 1
    command 2
  if not "%count2%%count1%"=="+++-------" %then% goto end
  %else% if not "%count1%"=="-------" %then% goto loop
         %else% set count2=%count2%+| set count1=
         goto loop

SHIFT

PAUSE [remark]

REM [remark]

Example: :label
         :comments
         .comments
         .comments %1 %2
            Command line parameters may be displayed on comment lines.
         REM comments
         echo         {bell}
         goto label
Example: copy con: %1     {enter text to files within a batch environment}
Example: REM CTRL-H CTRL-H CTRL-H comments   {not to show "REM" in echo mode}
Example: SET abc=\fortran\fortran.lib
         link %1,,,%abc%
Example: SET mouse=1      {set the environment in one batch file}
         IF %mouse%=="1" copy abc.txt com1:
Example: IF .%1==.abc dir {dots allow .BAT files to continue running when there
                          is no parameter passed.}
Example: IF dummy==dummy%1 GOTO label {test for nul parameter in a batch file}
                                      {good for terminating SHIFT}
Example: IF ERRORLEVEL 1 IF x==%1 command           зд
         IF ERRORLEVEL 1 IF EXIST filename command  юд{to nest IF statement}
Example: ECHO CTRL-H      {to output a blank line to the console}
Example: ECHO   A ... program1
         ECHO   B ... program2
         ECHO Press the letter of your selection
         PAUSE > select.bat
         select
Example: FOR %%f IN (*.*) DO program %%f {good for a program that cannot handle
                                          global chars * and ?}
         FOR %%f IN (*.*) DO type %%f
         FOR %%f IN (abc.hlp,command.hlp,batch.hlp) DO type %%f
         FOR %%f IN (*.g) DO ren %%f %%for    {ren all .g files to .gor}
         FOR %%f IN (*.hlp) DO find "abc" %%f {find "abc" in all the .hlp files}
Example: rem print a number of files with the corresponding directories & with formfeed
         echo off
         cls
         :loop
         echo ... PRINTING FILE %1
         dir %1|find "-" > prn:
         echo 
 > prn:                   {line feed}
         echo -------------------------------------------------------- > prn:
         echo 
 > prn:                   {line feed}
         copy %1 prn:
         echo  > prn:                   {form feed}
         shift                          {handle the next argument}
         if not dummy==dummy%1 goto loop
Example: GOTO f%1
         :fA
         echo the 1st argument was A
         GOTO end
         :fB
         echo the 1st argument was B
         GOTO end
         :fC
         echo the 1st argument was C
         :end

See BAT for a set of enhanced batch file commands.

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Computer Methods in Chemical Engineering -- Batch Commands
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Nam Sun Wang Department of Chemical & Biomolecular Engineering University of Maryland College Park, MD 20742-2111 301-405-1910 (voice) 301-314-9126 (FAX) e-mail: nsw@umd.edu ©1996-2006 by Nam Sun Wang