Auto refresh PDF as it is being changed

using Preview

use the following AppleScript and save it as ReloadPreviewDocument.scpt

Reload Preview Document 1.0
By Trevor Harmon <>

Based in part on the "Checking Accessibility Status" script by Apple.

on UIscript_check()
    -- get the system version
    set the hexData to system attribute "sysv"
    set hexString to {}
    repeat 4 times
        set hexString to ((hexData mod 16) as string) & hexString
        set hexData to hexData div 16
    end repeat
    set the OS_version to the hexString as string
    if the OS_version is less than "1030" then
        display dialog "This script requires Mac OS X 10.3 or higher." buttons {"Cancel"} default button 1 with icon 2
    end if
    -- check to see if assistive devices is enabled
    tell application "System Events"
        set UI_enabled to UI elements enabled
    end tell
    if UI_enabled is false then
        tell application "System Preferences"
            set current pane to pane ""
            display dialog "This script utilizes the built-in Graphic User Interface Scripting architecture of Mac OS X which is currently disabled." & return & return & "You can activate GUI Scripting by selecting the checkbox \"Enable access for assistive devices\" in the Universal Access preference pane." with icon 1 buttons {"Cancel"} default button 1
        end tell
    end if
end UIscript_check

on reload_document(doc)

    -- Make sure the document in question is the frontmost window
    do shell script "open " & doc

    -- Now close it
    tell application "System Events"
        tell process "Preview"
            tell menu bar 1
                tell menu bar item "File"
                    tell menu 1
                        click menu item "Close"
                    end tell
                end tell
            end tell
        end tell
    end tell

    -- And finally reopen it
    do shell script "open " & doc

end reload_document

on run argv
    my UIscript_check()
    my reload_document(item 1 of argv)
end run

To open a pdf document with auto refresh do:

osascript "ReloadPreviewDocument.scpt" document.pdf

using TeXShop

make sure to enable Automatic Preview Update under Preferences → Preview → External Editor