Powershell export CSV list from files and folders in directory

dir -Recurse | Export-Csv files.csv

Disable SIP ALG in Cisco 1800 Series Router

no ip nat service sip udp port 5060
no ip nat service sip tcp port 5060

Batch file rename with random alphanumeric

The following simple script will rename all .jpg files in the current folder to random 8 character alphanumeric names, preserving the .jpg extension. Note that it is possible for the random name generator to produce a name that already exists, so the script loops until it successfully generates a unique name.

@echo off
setlocal disableDelayedExpansion
set "chars=ABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789"
for /f "eol=: delims=" %%F in ('dir /b /a-d *.jpg') do call :renameFile "%%F"
exit /b

:renameFile
setlocal enableDelayedExpansion
:retry
set "name="
for /l %%N in (1 1 8) do (
  set /a I=!random!%%36
  for %%I in (!I!) do set "name=!name!!chars:~%%I,1!"
)
echo if exist !name!.jpg goto :retry
endlocal & ren %1 %name%.jpg

A bit more code yields a versatile utility that allows you to specify the source path and file mask, and also provides the option to process sub-directories as well. The utility always preserves the extension of each file. Be careful with this utility!
renameFilesRandom.bat

:: renameFilesRandom.bat  [filter]  [/s]
@echo off
setlocal disableDelayedExpansion

:: Parse and validate arguments
set "option="
set "filter="
if "%~3" neq "" (
  >&2 echo ERROR: Too many arguments
  exit /b 1
)
if /i "%~1" equ "/S" (set "option=/S") else if "%~1" neq "" set "filter=%~1"
if /i "%~2" equ "/S" (set "option=/S") else if "%~2" neq "" (
  if defined filter (
    >&2 echo ERROR: Only one filter allowed
    exit /b 1
  ) else set "filter=%~2"
)
if "%filter:~0,1%" equ "/" (
  >&2 echo ERROR: Invalid option %filter%
  exit /b 1
)
if not defined filter set "filter=*"

:: Convert a directory filter into a file filter with wildcards
if exist "%filter%\" set "filter=%filter%\*"

:: Determine source if /S option not specified
set "src="
if not defined option for /f "eol=: delims=" %%F in ("%filter%") do set "src=%%~dpF"

:: Rename the specified files
set "chars=ABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789"
for /f "eol=: delims=" %%F in ('dir /a-d /b %option% "%filter%"') do call :renameFile "%%F"
exit /b

:renameFile
setlocal
if not defined src set "src=%~dp1"
set "old=%~nx1"
set "ext=%~x1"
setlocal enableDelayedExpansion
:retry
set "name="
for /l %%N in (1 1 8) do (
  set /a I=!random!%%36
  for %%I in (!I!) do set "name=!name!!chars:~%%I,1!"
)
if exist "!src!!name!!ext!" goto :retry
ren "!src!!old!" "!name!!ext!"

Below are some sample usages.
Rename all files in the current directory:

renameFilesRandom

Rename all .jpg files in the current directory:

renameFilesRandom *.jpg

Rename all .jpg files in the c:\test folder, and all its sub-folders (recursive):

renameFilesRandom c:\test\*.jpg /s

Directory.GetFiles () Order By Date

1. using System.Linq;
2.  
3. DirectoryInfo info = new DirectoryInfo("");
4. FileInfo[] files = info.GetFiles().OrderBy(p => p.CreationTime).ToArray();
5. foreach (FileInfo file in files)
6. {
7.     // DO Something...
8. }

How to execute ImageMagick to convert only the first page of the multipage PDF to JPEG?

If you are using a convert command line you can execute it with these parameters:

convert  source.pdf[0]  output.jpeg

Note that the page count of ImageMagick is 0-based. So [0] means 'page 1'. To select, say the 4th page, you'd have to use [3].

This syntax does not only work for PDF input. It also works with other multi-page or mult-frame formats, such as multi-page TIFF or animated multi-frame GIFs and PNGs.

Process.Start Method

using System.Diagnostics;

class Program
{
    static void Main()
    {
        LaunchCommandLineApp();
    }

    /// <summary>
    /// Launch the legacy application with some options set.
    /// </summary>
    static void LaunchCommandLineApp()
    {
        // For the example.
        const string ex1 = "C:\\";
        const string ex2 = "C:\\Dir";

        // Use ProcessStartInfo class.
        ProcessStartInfo startInfo = new ProcessStartInfo();
        startInfo.CreateNoWindow = false;
        startInfo.UseShellExecute = false;
        startInfo.FileName = "dcm2jpg.exe";
        startInfo.WindowStyle = ProcessWindowStyle.Hidden;
        startInfo.Arguments = "-f j -o \"" + ex1 + "\" -z 1.0 -s y " + ex2;

        try
        {
            // Start the process with the info we specified.
            // Call WaitForExit and then the using-statement will close.
            using (Process exeProcess = Process.Start(startInfo))
            {
                exeProcess.WaitForExit();
            }
        }
        catch
        {
            // Log error.
        }
    }
}

Extract Pages From a PDF

https://www.linuxjournal.com/content/tech-tip-extract-pages-pdf

There are a number of ways to extract a range of pages from a PDF file: there are PDF related toolkits for doing it, or you can use Ghostscript directly.

For example, to extract pages 22-36 from a 100-page PDF file using pdftk:

  $ pdftk A=100p-inputfile.pdf cat A22-36 output outfile_p22-p36.pdf

Or use a combination of xpdf-utils (or poppler-tools) with psutils and the ps2pdf command (which ships as part of Ghostscript):

  $ pdftops 100p-inputfile.pdf - | psselect -p22-36 | \
         ps2pdf14 - outfile_p22-p36.pdf

Or, just use Ghostscript (which, unlike pdftk, is installed nearly everywhere; and you've been using it in the last command anyway):

  $ gs -sDEVICE=pdfwrite -dNOPAUSE -dBATCH -dSAFER \
       -dFirstPage=22 -dLastPage=36 \
       -sOutputFile=outfile_p22-p36.pdf 100p-inputfile.pdf

Regarding speed and efficiency of the processing and more important the quality of the output file, the 2nd method above is for sure the worst of the 3. The conversion of the original PDF to PostScript and back to PDF (also known as "refrying" the PDF) is very unlikely to completely preserve advanced PDF features (such as transparency information, font hinting, overprinting information, color profiles, trapping instructions, etc.).

The 3rd method uses Ghostscript only (which the 2nd one uses anyway, because ps2pdf14 is nothing more than a wrapper script around a more or less complicated Ghostscript commandline. The 3rd method also preserves all the important PDF objects on your pages as they are, without any "roundtrip" conversions....

The only drawback of the 3rd method is that it's a longer, more complicated command line to type. But you can overcome that drawback if you save it as a bash function. Just put these lines in your ~/.bashrc file:

function pdfpextr()
{
    # this function uses 3 arguments:
    #     $1 is the first page of the range to extract
    #     $2 is the last page of the range to extract
    #     $3 is the input file
    #     output file will be named "inputfile_pXX-pYY.pdf"
    gs -sDEVICE=pdfwrite -dNOPAUSE -dBATCH -dSAFER \
       -dFirstPage=${1} \
       -dLastPage=${2} \
       -sOutputFile=${3%.pdf}_p${1}-p${2}.pdf \
       ${3}
}

Now you only need to type (after starting a new copy bash or sourcing .bashrc) the following:

  $ pdfpextr 22 36 inputfile.pdf

which will result in the file inputfile_p22-p36.pdf in the same directory as the input file.