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Did you ever want to execute a program on a LIST of files? DoList will execute a command line and substitute text from the standard input device in the command line. Suppose you have a file named "BAK.LST" that contains the following list of files:
NOTES.BAK JOBS.BAK AUTOEXEC.BAK CONFIG.BAKIf you want to delete all the files in the list you type:
DOLIST DEL @L < BAK.LST
or
TYPE BAK.LST|DOLIST DEL @L
DoList will then execute the following commands:
DEL NOTES.BAK DEL JOBS.BAK DEL AUTOEXEC.BAK DEL CONFIG.BAKDoList reads each line from the standard input device and executes the command for each line read. The @L causes DoList to insert the next input line into the command. Therefore, the command "DEL @L" is executed for each line from the standard input file, which in this case is BAK.LST.
Suppose you want to copy all your .BAT files on you hard disk to a floppy. This can be done by typing:
WHEREIS *.BAT|DOLIST COPY @L A:Adding @T to the command (WHEREIS *.BAT|DOLIST COPY @L A: @T) will cause DoList to type the commands instead of executing them. This output can be redirected into a file for later execution.
Summary of DoList Commands for LIST mode:
@L ;substitute next input line
@1 .. @9 ;substitute field 1 thru 9
@T ;output commands as text instead of executing them
@Q ;query mode, displays command and asks for confirmation
@[ ;substitutes < in command line
@] ;substitutes > in command line
@]] ;substitutes >> in command line
@! ;substitutes | in command line
{} ;commands in {braces} are not interpreted but passed as text
In addition to the @L command, which substitutes the whole line, DOLIST
can look at the lines as fields that can be substituted individually.
The individual fields are substituted by @1 thru @9. In the text line:
456,NOTES.TXT "Marc Perkel"The rule is: commas and spaces are delimiters (characters used to separate fields or parameters) unless you start with a quote. If you start with a quote, the next quote is the delimiter.@1 = 456 @2 = NOTES.TXT @3 = Marc Perkel
If you don't want DoList to actually execute the commands, the @T command will cause DoList to output the text that it would have executed. This text can be redirected to a BAT file for later execution.
The @Q command makes DoList ask before executing each command line. This allows you to skip the command or abort DoList.
Example:Using braces '{}' suspends interpretation of @ commands allowing the @ to be part of the command. The outermost pair of braces are removed from the command. This is useful when using DoList recursively. That means using DoList to run DoList.
PIPEDIR *.BAT >BAT.LST Creates BAT.LST with list of all *.BAT files.
DOLIST COPY @IBAT.LST @L@T A: @OTEST.BAT Reads each line of BAT.LST and creates the command COPY [line] A: and writes these commands to a file named TEST.BAT.
When a command line is presented to DOS, the redirection and piping commands, [ ] | are interpreted and removed. In order to pass these commands to a program that DoList can run, we must use other codes that DOS won't remove. The @[ is translated into <, the @] is translated into >, the @]] is translated into >> and the @! is translated into |.
Using DoList Recursively:
Lets say we have a file named X.LST that contains the lines:
1 2 3And a file named Y.LST that contains the lines:
A B CThe following command produces the following results:
DOLIST DOLIST @L{@L@T}@[x.lst <y.lst
A1
A2
A3
B1
B2
B3
C1
C2
C3
In this example, the outer DoList causes the inner DoList to be executed
three times. It executes the lines:
DOLIST A@l@t<x.lst DOLIST B@l@t<x.lst DOLIST C@l@t<x.lstNotice that the outer DoList caused the first @L to be translated into A,B,C from Y.LST and that @[x.lst was translated into <x.lst. Also, note that the braces {} were removed but the interpretation of what was inside the braces is preserved for the inner DoList.
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