How define a big array in Batch? - arrays

I want to define a big array (>400 keys) in batch, but when I execute my script the windows close. I use this setting:
set FILE_LIST=(filename1.xxx [...] filename450.yyy)
Some help? Thx

A Windows Batch file have a limit in the value of each variable to 8192 characters, including the name of the variable and the equal sign. If the value of each "filename#.xxx " have 16 characters, you may store up to 8192/16=512 file names in one variable; to do that, you must use Batch commands. For example:
#echo off
setlocal EnableDelayedExpansion
set "FILE_LIST="
for /L %%i in (1,1,450) do set "FILE_LIST=!FILE_LIST!filename%%i.xxx "
echo FILE_LIST=%FILE_LIST%
Please, note that previous variable is a list, NOT and array. To define an array, use this method:
#echo off
setlocal EnableDelayedExpansion
for /L %%i in (1,1,450) do set "FILE_ARRAY[%%i]=filename%%i.xxx"
echo FILE_ARRAY:
set FILE_ARRAY
There is a limit of 64 MegaBytes for the total space occupied by all variables.
For a detailed description of arrays and other data structures in Batch files, see: Arrays, linked lists and other data structures in cmd.exe Batch script
EDIT: Reply to the comments
The Batch file below assume that there is one file name per line in the .txt file, and that file names does not include exclamation marks:
#echo off
setlocal EnableDelayedExpansion
rem Load the .txt file in FILE_ARRAY elements:
set num=0
for /F "delims=" %%a in (fileList.txt) do (
set /A num+=1
set "FILE_ARRAY[!num!]=%%a"
)
rem Process the FILE_ARRAY elements:
for /L %%i in (1,1,%num%) do echo Processing: %%i- "!FILE_ARRAY[%%i]!"

I finaly use this way:
set FILE_ARRAY[0]=filename1.xxx
set FILE_ARRAY[1]=filename2.yyy
set FILE_ARRAY[2]=filename3.zzz
for /F "tokens=2 delims==" %%i in ('set FILE_ARRAY[') do (
echo %%i
)
Thanks for your answers.

Seems like you might be hitting a batch file limitation (link), The following link describes a WA for this issue as dumping what you want in a var into a file, then reading that file back in when you need that massive var.
Ah batch, and your endless workarounds...

Related

Batch list all file extension in a specific directory

Using windows batch file, I am trying to echo a list of file extensions in a folder.
That will then be set as %var% and output to .txt file
#setlocal & #(for %%I in (*.*) do #set /a ext[%%~xI] += 1) & set ext[
from this post Windows command to get list of file extensions
My end game is I would like it to output like so
folder contents:
sample1.jpg
sample2.jpg
sample3.jpg
sample4.mp4
sample5.mp4
sample6.png
sample7.zip
sample8.zip
result:
.jpg, .mp4, .png, .zip
Any help is greatly appreciated, I hope I explained it clear enough
You already have defined a variable for each extension. Just use another for /f loop to concatenate the relevant part (the actual extension) of them:
#echo off
setlocal enabledelayedexpansion
for %%I in (*) do #set /a ext[%%~xI] += 1
for /f "tokens=2 delims=[]" %%a in ('set ext[') do set "var=%%a, !var!"
echo %var:~0,-2%
#setlocal ENABLEDELAYEDEXPANSION&#(for %%I in (*.*) do #set /a ext[%%~xI] += 1&IF DEFINED ext[all] (IF "!ext[all]!" equ "!ext[all]: %%~xI=!" SET "ext[all]=!ext[all]!, %%~xI") ELSE (SET "ext[all]= %%~xI"))&SET "ext[all]=!ext[all]:~1!"&set ext[
Why you want this all on one line, I've no idea.
Since you need to access the changed value of a variable within a loop, you need delayedexpansion. Note that Space.ext is appended each time a new extension is found, so there will be an extra space at the start of the list variable - hence the requirement to remove the first character before displaying the result.

loop over an array in a bat script [duplicate]

This question already has answers here:
Arrays, linked lists and other data structures in cmd.exe (batch) script
(11 answers)
Closed 2 years ago.
I'm new to bat scripting and I wanted to use an iterative loop in my script (something like this in javascript for example)
for(var i=0;i<n;i++){
//my code here
console.log("my tab ["+i+"] is:"+tab[i];
}
So, basicaly this is my bat script in a file called exctract_excel_info.bat:
#ECHO OFF
::setlocal enabledelayedexpansion
:start
ECHO "Hi it's MIBE in this script i will list all the files with the extention xlsx or xls">log.txt
:start_loop
echo Listing all files in the current directory %cd% >log.txt
ECHO ================== ======================>>log.txt
set "AllowExt= *.xls"
ECHO the variable AllowExt in the first instruction %AllowExt%>>log.txt
set theFileName="NONE"
set /a i = 0
for %%a in (%AllowExt%) do (
set /a i = i + 1
::echo Found the file: "%%a">>log.txt
set theFileName[%i%]=%%a
)
:end_loop
ECHO ============================================>>log.txt
ECHO "The value of i is %i%">>log.txt
ECHO ============================================>>log.txt
for /L %%x in (1,1,%i%) do (
ECHO found the file %theFileName[%%x]%>>log.txt
)
ECHO ============================================>>log.txt
timeout /t 2
ECHO Yo the file %theFileName[0]% will be passed as a parameter
ECHO The array of files %theFileName%>>log.txt
:run_node
node main.js "%theFileName[0]%">>log.txt
timeout /t 2
:end
::PAUSE
I have a problem reading the value of the variable theFileName[i] in line 32
ECHO found the file %theFileName[%%x]%>>log.txt
This is the output (log.txt):
Listing all files in the current directory C:\Users\mibe\my bat
================== ======================
the variable AllowExt in the first instruction *.xls
============================================
"The value of i is 4"
============================================
So my problem is what is the proper way to read the value of the items inside theFileName array?
PS: when I comment the lines 31, 32, and 33:
for /L %%it in (1,1,"%i%") do (
ECHO found the file %theFileName[%%it]%>>log.txt
)
the script executes properly and get the value of %theFileName[0]%
The following is a basic example of what I think you're trying to do, up to a point.
The problem is that because you've not told us what exactly you're intending to do with those similarly named variables, I cannot include the specific methodology for doing so. I have therefore just output the defined variable names along side their value strings.
#SetLocal EnableExtensions DisableDelayedExpansion
#For /F "Delims==" %%G In ('"(Set File[) 2> NUL"') Do #Set "%%G="
#Set "i=0" & For /F Delims^= %%G In (
'"(Set PATHEXT=) & "%__APPDIR__%where.exe" ".:*.xlsx" ".:*.xls" ".:*.csv" 2> NUL | "%__AppDir__%sort.exe""'
) Do #(Set /A i += 1 & SetLocal EnableDelayedExpansion
For %%H In (!i!) Do #EndLocal & Set "File[%%H]=%%~nxG")
#If Defined File[1] For /L %%G In (1,1,%i%) Do #(SetLocal EnableDelayedExpansion
Echo File[%%G]=!File[%%G]! & EndLocal)
#Pause
The code above should define individual variables, each containing the string value of a file in the current directory, which has an extension of either .xlsx, .xls, or .csv.
When I first looked at your question I initially thought that you were intending to pass each file name together as multiple arguments to your node command.
If that is what you're actually intending to do, then I'd assume the following example would suit your purposes better.
#SetLocal EnableExtensions DisableDelayedExpansion
#Set "FileList="&For /F Delims^= %%G In (
'"(Set PATHEXT=) & "%__APPDIR__%where.exe" ".:*.xlsx" ".:*.xls" ".:*.csv" 2> NUL | "%__AppDir__%sort.exe""'
) Do #If Not Defined FileList (Set "FileList="%%~nxG"") Else (SetLocal EnableDelayedExpansion
For /F Delims^=^ EOL^= %%H In ("!FileList!") Do #EndLocal & Set "FileList=%%H "%%~nxG"")
#If Defined FileList Echo %%FileList%%=%FileList%
#Pause
The code above should define a single variable, containing the space separated, and doublequoted, string values, of each file in the current directory, which has an extension of either .xlsx, .xls, or .csv.
Please note that there is a command line length limitation so be aware that your value could become truncated.
In both examples:
The last line, #Pause, is included only to prevent premature closure of the cmd window, should you not be testing this from the CLI. (You can safely remove it if you are).
I assumed you wanted only the filenames without their paths, in the variable values. Should you wish for the full paths, just change %%~nxG in your chosen example code to %%G.
BTW, I used sort.exe against the returned files, because you mentioned array, and IMO an array should be ordered. (If you do not need that functionality, you could remove | "%__AppDir__%sort.exe" from your chosen example code).
Please note that there is a limit to the size of the environment, so be aware that if you have many matching files, they have long filenames, include paths etc. you may reach or exceed that limitation.
Having provided some examples for you, I'm not sure why you could not just iterate your directory, and create an array of those files, directly using .js, (off topic).

Nested /F looping and If statements in batch file

I have two .txt files. One contains numbers, and the other one contains filepaths. I want to combine these two files to a .csv. The combination is based on wether the number (from nrs.txt) is in the string of the filepath (nodups.txt).
Now I have the following code for this:
#setlocal enableextensions enabledelayedexpansion
for /F %a IN (Output\nrs.txt) DO (
SET "nrs=%a"
for /F %b IN (Output\nodups.txt) DO (
SET "pathstring=%b"
SET csvdelim=,
IF NOT x!pathstring:%nrs%=""!==x%pathstring% %nrs%,%pathstring%>>new2017.txt
)
)
#endlocal
However, I keep having the following issues with the code:
The pathstring never seems to get set. (when I run the code without the if statement, The nrs variable gets set but the pathstring is set to %b). I've seen a lot of possible solutions on here already but none seem to work for me (setting variables like !var! and using usebackq).
The IF statement in the second for loop gets the following error message =""!==x%pathstring% was unexpected at this time. The ="" should remove the nr. from the path (if its there). When I replace "" with something else it still does not work.
The file contents are:
File nrs.txt:
12345
12245
16532
nodubs.txt:
C:\tmp\PDF_16532_20170405.pdf
C:\tmp\PDF_1234AB_20170405.pdf
C:\tmp\PDF_12345_20170506.pdf
Desired output:
12345, C:\tmp\PDF_12345_20170506.pdf
16532, C:\tmp\PDF_16532_20170405.pdf
I really hope someone can help me out with this !
This solution use a different approach, based on arrays:
#echo off
setlocal EnableDelayedExpansion
rem Load array from nodubs.txt file
pushd "Output"
for /F "tokens=1,2* delims=_" %%a in (nodubs.txt) do set "nodubs[%%b]=%%a_%%b_%%c"
rem Process nrs.txt file and show output
(for /F %%a in (nrs.txt) do (
if defined nodubs[%%a] echo %%a, !nodubs[%%a]!
)) > new2017.txt
In a batch file for variables need two percent signs.
There is no need to put %%A into a variable, use it directly.
#setlocal enableextensions enabledelayedexpansion
for /F %%a IN (Output\nrs.txt) DO (
findstr /i "_%%a_" Output\nodups.txt >NUL 2>&1 || >>new2017.txt Echo %%a
)
#endlocal
Instead of a second for, I'd use findstr to search for the entry of nrs.txt enclosed in underscores.
if no find use condiotonal execution on failure || to write to the new file.
According to changed preliminaries another answer.
#Echo on
Pushd Output
for /F "tokens=1-3 delims=_" %%A IN (
' findstr /G:nrs.txt nodubs.txt'
) DO >>"..\new2017.txt" Echo %%B, %%A_%%B_%%C
Popd
sample output:
> type ..\new2017.txt
16532, C:\tmp\PDF_16532_20170405.pdf
12345, C:\tmp\PDF_12345_20170506.pdf

Batch file to create multiple variables from single lines in a text file

I have a text file with the names of computer names and corresponding static i.p. addresses in the following format.
COMPUTER NAME:PC ADDRESS=154.100.1.1 MASK=255.255.254.0
COMPUTER NAME:PC2 ADDRESS=100.100.1.1 MASK=255.255.254.0
I would like to take the values from each line and put them as variables in a batch file for use later. Is this possible? The overall goal is to have the values from this easily edited text file to be used in netsh commands in another batch file.
I've looked around and found ways to take lines of a text file and place them in one variable using the snippet below. However, I do not know how to create multiple variables from one line. If someone could help me with this I'd greatly appreciate it!
#echo o
setlocal enabledelayedexpansion
set Counter=1
for /f %%x in (D:\COMP_T.txt) do (
set "comp!Counter!=%%x"
set /a Counter+=1
)
This should work:
#echo off
setlocal EnableDelayedExpansion
set "Count=1"
for /f "tokens=1,2,3,4,5,6,7 delims==: " %%A in (C:\File.txt) do (
set "%%A[!Count!]=%%C"
set "%%D[!Count!]=%%E"
set "%%F[!Count!]=%%G"
set /a "Count+=1"
)
:: Call other batch script here.
endlocal
Example Output:
COMPUTER[1]=PC
COMPUTER[2]=PC2
ADDRESS[1]=154.100.1.1
ADDRESS[2]=100.100.1.1
MASK[1]=255.255.254.0
MASK[2]=255.255.254.0
Here is a solution that avoids the need for delayed expansion. It uses FINDSTR to insert a line number followed by : at the beginning of each line. The search string of "^" is guaranteed to match every line in the file.
The only other issue is to set TOKENS and DELIMS to parse the line properly.
#echo off
setlocal
for /f "tokens=1,4,6,8 delims=:= " %%A in ('findstr /n "^" "d:\comp_t.txt"') do (
set "comp%%A=%%B"
set "addr%%A=%%C"
set "mask%%A=%%D"
set "counter=%%A"
)
To use the set of variables in another batch file, line by line, just parse the lines as done in other answers here, and call the other batch file with the metavariables.
#echo off
for /f "tokens=1,2,3,4,5,6,7 delims==: " %%a in ('type "File.txt" ') do (
echo "computer_name=%%c"
echo "address=%%e"
echo "mask=%%g"
Call "batch script" "%%c" "%%e" "%%g"
)

How to change the order of lines in a file using a batch script?

A have a text file that contains the results of a dir
dir "%local%" /b /a:d /s >> FolderList.txt
But I want to iterate in a For loop going from the last to the first line.
Since I believe this cannot be done in the For command, how can I generate a new file containing the same lines but in a inverse order?
You can't using the For command. But you can reverse the order of the dir listing that created the text file, using dir "%local%" /o-n /b /a:d /s >> FolderList.txt; the - means "reversed".
I like the general strategy of both of Aacini's original solutions, but as written they have problems (some trivial, some significant)
Original Aacini solution 1 using temp file with SORT:
Corrupts lines containing exclamation point (!)
Strips leading colon(s) (:) from each line
temp file creation using >> not as efficient as >
Uses default SORT maximum line length of 4096 bytes
Line count unnecessarily capped at 1 million
Doesn't actually provide the asked for solution (an actual file output)
Leaves behind the temporary file
Modified solution 1
Here is a version that fixes the problems. The only practical limitation is a maximum line length of 8180 bytes (characters). I'm not sure how high FINDSTR can count, but this solution will handle up to 999 billion lines. (I agree with Aacini, no one would ever want to wait for such a large file to finish using a batch solution) The line limit can easily be adjusted.
#echo off
setlocal DisableDelayedExpansion
set file="%~1"
set revfile="%~1.rev"
set tempfile="%temp%\revfile%random%.txt"
(
for /f "delims=" %%a in ('findstr /n "^" %file%') do (
set "ln=%%a"
setlocal EnableDelayedExpansion
for /f "delims=:" %%n in ("!ln!") do set "prefix=000000000000%%n"
echo !prefix:~-12!!ln:*:=!
endlocal
)
)>%tempfile%
(
for /f "delims=" %%a in ('sort /rec 8192 /r %tempfile%') do (
set "ln=%%a"
setlocal EnableDelayedExpansion
echo(!ln:~12!
endlocal
)
)>%revfile%
del %tempfile%
Aacini modified solution 1
Aacini dramatically improved the robustness and performance with a modified solution 1 using SET /P and multiple TEMP files. The SET /P solution eliminates the need for a looped SETLOCAL/ENDLOCAL toggle, but it does have a few limitations.
Lines must be terminated by <LF><CR> (normal for Windows, but Unix style is sometimes encountered in Windows world).
Lines must be <= 1024 characters
Control characters at end of line will be stripped.
Modified solution 1 take 2
If any of the above limitations are a problem, here is an adaptation of my 1st solution that uses multiple temp files. Like Aacinis modified solution, it performs linearly with file size. It is about 40% slower than Aacinis modified version.
#echo off
setlocal DisableDelayedExpansion
set file="%~1"
set revfile="%~1.rev"
set "tempfile=%temp%\revfile%random%.txt"
findstr /n "^" %file% >"%tempfile%.1"
(
for /f "usebackq delims=" %%a in ("%tempfile%.1") do (
set "ln=%%a"
setlocal EnableDelayedExpansion
for /f "delims=:" %%n in ("!ln!") do set "prefix=000000000000%%n"
echo !prefix:~-12!!ln:*:=!
endlocal
)
)>"%tempfile%.2"
sort /rec 8192 /r "%tempfile%.2" >"%tempfile%.3"
(
for /f "usebackq delims=" %%a in ("%tempfile%.3") do (
set "ln=%%a"
setlocal EnableDelayedExpansion
echo(!ln:~12!
endlocal
)
)>%revfile%
del "%tempfile%*"
Original Aacini solution 2 using environment variables:
Corrupts lines containing exclamation point (!)
Strips blank lines
Doesn't actually provide the asked for solution (an actual file output)
Modified solution 2
Here is a version that fixes the problems. The only known limitations are
A maximum line length between 8181 and 8190, depending on line number
A maximum file size slightly under 64MB.
This was my favorite solution because the file output can probably be eliminated by processing the file in the variables directly, thus completely avoiding the creation of any temporary file. Edit But based on info provided by Aacini, I learned it has severe performance problems as the environment grows. The problem is worse than Aacini realized - Even a simple SET command suffers dramatically with large environment sizes. I've posted a question regarding this phenomenon at DosTips. http://www.dostips.com/forum/viewtopic.php?f=3&t=2597 (I originally posted on SO, but apparently the question is too open ended for this site)
#echo off
setlocal disableDelayedExpansion
set file="%~1"
set revfile="%~1.rev"
set num=0
for /f "delims=" %%a in ('findstr /n "^" %file%') do (
set /a "num+=1"
set "ln=%%a"
setlocal enableDelayedExpansion
for %%n in (!num!) do for /f "delims=" %%b in (""!ln:*:^=!"") do endlocal&set "ln%%n=%%~b"'
)
setlocal enableDelayedExpansion
(
for /l %%n in (!num! -1 1) do echo(!ln%%n!
)>%revfile%
There are two relatively easy ways to sort a file in reversed order. The first one is a direct method over file contents: add line numbers to all lines, sort the file in reversed order, eliminate line numbers:
#echo off
setlocal EnableDelayedExpansion
rem Insert line numbers in all lines
for /F "tokens=1* delims=:" %%a in ('findstr /n ^^ %1') do (
set /A lineNo=1000000+%%a
echo !lineNo!:%%b>> tempfile.txt
)
rem Sort the file and show the result
for /F "tokens=1* delims=:" %%a in ('sort /r tempfile.txt') do (
echo Line %%a is %%b
)
The other method consist in load the file lines in a Batch array, that may be processed in any way you wish:
#echo off
setlocal EnableDelayedExpansion
rem Load file lines in a Batch array
set lineNo=0
for /F "delims=" %%a in (%1) do (
set /A lineNo+=1
set "line[!lineNo!]=%%a"
)
rem Process array elements in reversed order:
for /L %%i in (%lineNo%,-1,1) do (
echo Line %%i is !line[%%i]!
)
This last method works only if the size of the file is below 64 MB, because this is the limit for Batch variables.
Both methods can be modified to correctly process special characters (> < |).
HOWEVER
If you want to delete all the tree contents of a folder in bottom-up order, the "right" way to do that is via a recursive subroutine...
EDIT Answer to dbenham
As I wrote in my answer, the two methods I proposed can be modified to correctly process special characters and blank lines. In my answer I showed a general method to "change the order of lines" in reversed order paying no special attention on create an output file because the OP said in his own answer that "The objective was to reorder a list of folders to prevent problems while deleting them in sequence", so I thought that was enough to show him how to process the folders in reversed order. I also assumed that the list of folders:
Have not exclamation points (!).
Have not leading colons (:).
Folder names are shorter than 4096 bytes.
Have less than 1000000 lines.
Have not blank lines.
I even thought (and still think) that the method the OP want to use to delete a list of folders is not adequate, and I mentioned this point under a big HOWEVER in my answer proposing to use a recursive subroutine instead.
However it seems that dbenham thought that the original question was something similar to "What is the most efficient method to sort a large file in reversed order?" and criticize my methods because they lack of such features. For this reason, I should reply in terms of this new question (efficient method), right?
In first place, it's funny to me that dbenham critizice my methods because "Doesn't actually provide the asked for solution (an actual file output)", but in his own Modified solution 2 he wrote that "This is my favorite solution because the file output can probably be eliminated by processing the file in the variables directly, thus completely avoiding the creation of any temporary file". ???
The two methods proposed by dbenham have a serious problem in terms of efficiency that was already discussed in this question: the pair of setlocal EnableDelayedExpansion and endlocal commands are executed with every line of the file. If the file is large (i.e. 200 000 lines and about 8 MB, as in the previous mentioned question) the environment will be copied to a new memory area and then deleted, and this will be repeated for 200000 times! Of course, this task is time-consuming. This problem becomes worse in dbenham's Modified solution 2: as the processing of lines go on, the environment grow as it store the file contents at that point. In the last lines of the file an environment almost equal to the size of the whole file will be copied to a new memory area for every remaining line of the file. Of course, this is the worst way to achieve this process in terms of efficiency!
There is another way to process empty lines and special characters that don't require the setlocal EnableDelayedExpansion - endlocal pair. For details on this method and further discussion on efficient ways to process large files, see the previously mentioned question.
The following Batch files are my modified versions on "How to sort a large file in reversed order in an efficient way".
Modified solution 1: using temp file with SORT
#echo off
setlocal EnableDelayedExpansion
set revfile="%~1.rev"
set tempfile=%temp%\revfile%random%
rem Insert line numbers in all lines
findstr /n ^^ %1 > "%tempfile%1.txt"
find /c ":" < "%tempfile%1.txt" > "%tempfile%2.txt"
set /P lines=< "%tempfile%2.txt"
call :JustifyLineNumbers < "%tempfile%1.txt" > "%tempfile%2.txt"
del "%tempfile%1.txt"
rem Sort the file in reversed order
sort /rec 8192 /r "%tempfile%2.txt" /o "%tempfile%3.txt"
del "%tempfile%2.txt"
rem Remove line numbers
call :RemoveLineNumbers < "%tempfile%3.txt" > %revfile%
del "%tempfile%3.txt"
goto :EOF
:JustifyLineNumbers
for /L %%i in (1,1,%lines%) do (
set /A lineNo=1000000000+%%i
set /P line=
echo !lineNo!!line:*:=!
)
exit /B
:RemoveLineNumbers
for /L %%i in (1,1,%lines%) do (
set /P line=
echo !line:~10!
)
exit /B
This solution still have a limit of "only" 1147483647 lines (the maximum 32-bits signed positive integer minus the initial seed). Although this limit can be easily increased in the way suggested by dbenham, that modification imply a slower execution speed. The conclusion is: if you really want to reverse-sort a very large file don't use a Batch file, but a more efficient programming language (like C).
Modified solution 2: using a Batch variable array
#echo off
setlocal EnableDelayedExpansion
set revfile="%~1.rev"
set tempfile=%temp%\revfile%random%
rem Load file lines in a Batch array
findstr /n ^^ %1 > "%tempfile%1.txt"
find /c ":" < "%tempfile%1.txt" > "%tempfile%2.txt"
set /P lines=< "%tempfile%2.txt"
del "%tempfile%2.txt"
call :CreateArray < "%tempfile%1.txt"
del "%tempfile%1.txt"
rem Process array elements in reversed order:
(for /L %%i in (%lines%,-1,1) do echo=!ln%%i!) > %revfile%
goto :EOF
:CreateArray
for /L %%i in (1,1,%lines%) do (
set /P line=
set ln%%i=!line:*:=!
)
exit /B
EDIT A possible solution for large environment problem.
I devised an idea that may solve, at least in part, the performance problems of SET command caused by a very large environment. Let's suppose that the internal operation of SET VAR=VALUE command follow these steps:
When a new variable is defined with a value that exceed the current environment size, the environment is copied to a new area if the area beyond it is not available.
The new area is just large enough to receive the new variable. No additional space is reserved.
The important one: When a large variable is deleted, the remaining free space is NOT released. The environment memory block is never shrunk.
If previous steps are true, then the performance problems may decrease if we first reserve the desired environment space via large (8 KB) variables with the same name of the working variables. For example, to reserve 1024 KB we define 128 large variables; I suppose that the time required to define these 128 variables will be less than the time required to fill the same 1024 KB with shorter variables.
When the process is running, the definition of the first 128 working variables will take the time necessary to delete an 8 KB variable and define a shorter one, but for the variable 129 on the process must be faster because it just define a new variable in an already available space. To aid to this process, the variables must have names that place them at the end of the environment as dbenham indicated.
:ReserveEnvSpace sizeInKB
rem Define the first large variable (reserving 6 bytes for variable name)
rem (this method may be done in larger chunks until achieve the fastest one)
set z1=X
for /L %%i in (1,1,8184) do set z1=!z1!X
rem Define the rest of large variables
set /A lastVar=%1 / 8
for /L %%i in (2,1,%lastVar%) do set z%%i=!z1!
exit /B
You may use MEM /P command to check the size and placement of the environment memory block. In old MS-DOS (command.com) days the environment was placed after command.com, but if a resident program was placed after the environment, then it can't grow anymore. For this reason, the /E:nnnnn switch was provided in command.com to reserve a certain size in bytes for the environment.
I have no time to check this method for the rest of the day, but here it is for you!
The objective was to reorder a list of folders to prevent problems while deleting them in sequence.
I came up with the following algorithm. I accept suggestions to make it more efficient or better.
#ECHO off
setLocal EnableDelayedExpansion
:: File that contains a list of folders
set file_from=%~1
:: Destination file, that will contain the sorted list
if "%2"=="" (
set replace=1
set file_to=_%file_from%
) else (
set file_to=%~2
)
:: Create empty destination file
if exist "%file_to%" del "%file_to%"
copy NUL "%file_to%"
:: Temporary file
if exist ".\~Remaining.txt" del ".\~Remaining.txt"
copy "%file_from%" .\~Remaining.txt
:: Sort the order of folders
:while
set untouched=1
For /f "tokens=* delims=" %%a in (.\~Remaining.txt) Do (
:: check if line was already added
FindSTR /X /C:%%a "%file_to%"
if errorlevel 1 (
set untouched=0
:: check if folder contains sub-folders to be added
FindSTR /B /C:%%a\ .\~Remaining.txt
if errorlevel 1 (
:: remove current line from "~Remaining.txt"
FindSTR /V /B /E /C:%%a .\~Remaining.txt> .\~Remaining_new.txt
move .\~Remaining_new.txt .\~Remaining.txt
:: add current line to destination file
>> "%file_to%" ECHO %%a
goto while
)
)
)
if untouched LSS 1 (
goto while
)
if exist .\~Remaining.txt del .\~Remaining.txt
if defined replace (
ECHO REPLACE!
:: destination was not provided, so replace
if exist "%file_from%" del "%file_from%"
move "%file_to%" "%file_from%"
)
This code will reverse a text file, but with a few limitations. Blank lines are omitted and lines containing special charaters cause it to fail: & < > |
#Echo Off
If "%1"=="" Goto Syntax
If "%2"=="" Goto Syntax
If Not Exist %1 (
Echo File not found: %1
Exit /B 2
)
SetLocal EnableDelayedExpansion
Set SOF=~StartOfFile~
Set InFile=%~snx1~in
Set OutFile=%2
Set TempFile=%~snx1~temp
If Exist %OutFile% Del %OutFile%
If Exist %TempFile% Del %TempFile%
Copy %1 %InFile% >nul
:Loop
Set "Line=%SOF%"
For /F "tokens=*" %%a In (%InFile%) Do (
If Not "!Line!"=="%SOF%" Echo !Line!>>%TempFile%
Set "Line=%%a"
)
Echo %Line%>>%OutFile%
Del %InFile%
If Not Exist %TempFile% (
EndLocal
Exit /B 0
)
Rename %TempFile% %InFile%
Goto Loop
:Syntax
Echo Usage:
Echo %~n0 input-file output-file
Echo.
Exit /B 1

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