add option to select components to install

see #25

README.md

@@ -10,29 +10,47 @@ Description
 
 Many components were removed in recent versions of Xcode, the most notable being the Mac OS X 10.6 SDK, which is required to build software using the Carbon API (such as wxWidgets 2.8).
 
-I made the script XcodeLegacy.sh to extract these components (the links work if you [sign in to Apple Developer](https://developer.apple.com/downloads/) first) from [Xcode 3.2.6](http://adcdownload.apple.com/Developer_Tools/xcode_3.2.6_and_ios_sdk_4.3__final/xcode_3.2.6_and_ios_sdk_4.3.dmg) (10.4, 10.5 and 10.6 SDKs, PPC assembler, GCC 4.0 and 4.2, LLVM-GCC 4.2), [Xcode 4.6.3](http://adcdownload.apple.com/Developer_Tools/xcode_4.6.3/xcode4630916281a.dmg) (10.7 SDK), [Xcode 5.1.1](http://adcdownload.apple.com/Developer_Tools/xcode_5.1.1/xcode_5.1.1.dmg) (10.8 SDK), [Xcode 6.4](http://adcdownload.apple.com/Developer_Tools/Xcode_6.4/Xcode_6.4.dmg) (10.9 and 10.10 SDKs) and install them in Xcode 4/5/6/7:
+I made the script XcodeLegacy.sh to extract these components (the links work if you [sign in to Apple Developer](https://developer.apple.com/downloads/) first) from [Xcode 3.2.6](https://developer.apple.com/devcenter/download.action?path=/Developer_Tools/xcode_3.2.6_and_ios_sdk_4.3__final/xcode_3.2.6_and_ios_sdk_4.3.dmg) (10.4, 10.5 and 10.6 SDKs, PPC assembler, GCC 4.0 and 4.2, LLVM-GCC 4.2), [Xcode 4.6.3](https://developer.apple.com/devcenter/download.action?path=/Developer_Tools/xcode_4.6.3/xcode4630916281a.dmg) (10.7 SDK), [Xcode 5.1.1](https://developer.apple.com/devcenter/download.action?path=/Developer_Tools/xcode_5.1.1/xcode_5.1.1.dmg) (10.8 SDK), [Xcode 6.4](https://developer.apple.com/devcenter/download.action?path=/Developer_Tools/Xcode_6.4/Xcode_6.4.dmg) (10.9 and 10.10 SDKs) and install them in Xcode 4/5/6/7:
 
 - GCC 4.0, GCC 4.2 and LLVM GCC 4.2 compilers
 - GCC 4.0, GCC 4.2 and LLVM GCC 4.2 Xcode plugins
 - PPC assembler
 - Mac OS X SDK 10.4u, 10.5, 10.6, 10.7, 10.8, 10.9, 10.10
 
-In order to re-enable the GCC 4.2 plugin in Xcode 4, you may also want to edit "/Applications/Xcode.app/Contents/PlugIns/Xcode3Core.ideplugin/Contents/SharedSupport/Developer/Library/Xcode/Plug-ins/GCC 4.2.xcplugin/Contents/Resources/GCC 4.2.xcspec" and change ShowInCompilerSelectionPopup to "YES" and IsNoLongerSupported to "NO".
+In order to re-enable the GCC 4.2 plugin in Xcode 4-7, you may also want to edit "/Applications/Xcode.app/Contents/PlugIns/Xcode3Core.ideplugin/Contents/SharedSupport/Developer/Library/Xcode/Plug-ins/GCC 4.2.xcplugin/Contents/Resources/GCC 4.2.xcspec" and change ShowInCompilerSelectionPopup to "YES" and IsNoLongerSupported to "NO".
 
 Note: There may be similar tips to compile for older iOS (not Mac OS X) versions, but I don't develop for iOS. However, if you want to enhace the XcodeLegacy script to also include those components, I'll gladly integrate your modifications.
 
 Download
 --------
-[XcodeLegacy.sh](http://devernay.free.fr/hacks/xcodelegacy/XcodeLegacy.sh) (previous versions: [1.0](http://devernay.free.fr/hacks/xcodelegacy/XcodeLegacy-1.0.sh), [1.1](http://devernay.free.fr/hacks/xcodelegacy/XcodeLegacy-1.1.sh), [1.2](http://devernay.free.fr/hacks/xcodelegacy/XcodeLegacy-1.2.sh))
+[XcodeLegacy.sh](http://devernay.free.fr/hacks/xcodelegacy/XcodeLegacy.sh) (previous versions: [1.0](http://devernay.free.fr/hacks/xcodelegacy/XcodeLegacy-1.0.sh), [1.1](http://devernay.free.fr/hacks/xcodelegacy/XcodeLegacy-1.1.sh), [1.2](http://devernay.free.fr/hacks/xcodelegacy/XcodeLegacy-1.2.sh),  [1.3](http://devernay.free.fr/hacks/xcodelegacy/XcodeLegacy-1.3.sh), [1.4](http://devernay.free.fr/hacks/xcodelegacy/XcodeLegacy-1.4.sh),  [1.5](http://devernay.free.fr/hacks/xcodelegacy/XcodeLegacy-1.5.sh), [1.6](http://devernay.free.fr/hacks/xcodelegacy/XcodeLegacy-1.6.sh),  [1.7](http://devernay.free.fr/hacks/xcodelegacy/XcodeLegacy-1.7.sh), [1.8](http://devernay.free.fr/hacks/xcodelegacy/XcodeLegacy-1.8.sh))
 
 [GitHub repository](https://github.com/devernay/xcodelegacy)
 
 Usage
 -----
-Execute the script in a terminal. The script takes one argument, which can be "buildpackages" (to extract components from the legacy Xcode downloads to the current directory), "install" (to install the components in Xcode 4/5/6), "cleanpackages" (to delete the extracted components from the current directory), "uninstall" (to uninstall the components from Xcode 4/5/6).
+
+Open a Terminal application, change to the directory where `XcodeLegacy.sh`, and make it executable, as in:
+```
+cd path/to/xcodelegacy
+chmod +x XcodeLegacy.sh
+```
+Execute the script by typing `./XcodeLegacy.sh <arg>`. The script takes one argument, which can be "buildpackages" (to extract components from the legacy Xcode downloads to the current directory), "install" (to install the components in Xcode 4/5/6), "cleanpackages" (to delete the extracted components from the current directory), "uninstall" (to uninstall the components from Xcode 4/5/6).
 
 With the "install" or "uninstall" arguments, the script uses sudo to become root, and will thus ask for your password. Please check the script contents before executing it.
 
+Optionally, one of the following options can be passed as the *first* argument to `XcodeLegacy.sh`, to limit its operation:
+
+* `-compilers` : only install the gcc and llvm-gcc compilers, as well as the corresponding Xcode plugins
+* `-osx104` : only install Mac OSX 10.4 SDK
+* `-osx105` : only install Mac OSX 10.5 SDK
+* `-osx106` : only install Mac OSX 10.6 SDK
+* `-osx107` : only install Mac OSX 10.7 SDK
+* `-osx108` : only install OSX 10.8 SDK
+* `-osx109` : only install OSX 10.9 SDK
+* `-osx1010` : only install OSX 10.10 SDK
+
+
 Using the older SDKs
 --------------------
 
@@ -60,12 +78,12 @@ Note on Xcode versions
 
 Here are the latest versions of Xcode that are known to /run/ on each OS X version (the links work if you [sign in to Apple Developer](https://developer.apple.com/downloads/) first):
 
-- [Xcode 3.1.4](http://adcdownload.apple.com/Developer_Tools/xcode_3.1.4_developer_tools/xcode314_2809_developerdvd.dmg) on Mac OS X 10.5 (Leopard)
-- [Xcode 3.2.6](http://adcdownload.apple.com/Developer_Tools/xcode_3.2.6_and_ios_sdk_4.3__final/xcode_3.2.6_and_ios_sdk_4.3.dmg) on Mac OS X 10.6 (Snow Leopard) - [Xcode 4.0.2](http://adcdownload.apple.com/Developer_Tools/xcode_4.0.2_and_ios_sdk_4.3/xcode_4.0.2_and_ios_sdk_4.3.dmg), [Xcode 4.1](http://adcdownload.apple.com/Developer_Tools/xcode_4.1_for_snow_leopard_21110/xcode_4.1_for_snow_leopard.dmg) and [Xcode 4.2](http://adcdownload.apple.com/Developer_Tools/xcode_4.2_with_ios_5_sdk/xcode_4.2_and_ios_5_sdk_for_snow_leopard.dmg) also run on Snow Leopard, but are only available to pay members 
-- [Xcode 4.6.3](http://adcdownload.apple.com/Developer_Tools/xcode_4.6.3/xcode4630916281a.dmg) on OS X 10.7 (Lion)
-- [Xcode 5.1.1](http://adcdownload.apple.com/Developer_Tools/xcode_5.1.1/xcode_5.1.1.dmg) on OS X 10.8 (Mountain Lion)
-- [Xcode 6.2](http://adcdownload.apple.com/Developer_Tools/Xcode_6.2/Xcode_6.2.dmg) on OS X 10.9 (Mavericks)
-- [Xcode 7.2.1](http://adcdownload.apple.com/Developer_Tools/Xcode_7.2.1/Xcode_7.2.1.dmg) on OS X 10.10 (Yosemite) and OS X 10.11 (El Capitan)
+- [Xcode 3.1.4](https://developer.apple.com/devcenter/download.action?path=/Developer_Tools/xcode_3.1.4_developer_tools/xcode314_2809_developerdvd.dmg) on Mac OS X 10.5 (Leopard)
+- [Xcode 3.2.6](http://developer.apple.com/devcenter/download.action?path=/Developer_Tools/xcode_3.2.6_and_ios_sdk_4.3__final/xcode_3.2.6_and_ios_sdk_4.3.dmg) on Mac OS X 10.6 (Snow Leopard) - [Xcode 4.0.2](https://developer.apple.com/devcenter/download.action?path=/Developer_Tools/xcode_4.0.2_and_ios_sdk_4.3/xcode_4.0.2_and_ios_sdk_4.3.dmg), [Xcode 4.1](https://developer.apple.com/devcenter/download.action?path=/Developer_Tools/xcode_4.1_for_snow_leopard_21110/xcode_4.1_for_snow_leopard.dmg) and [Xcode 4.2](https://developer.apple.com/devcenter/download.action?path=/Developer_Tools/xcode_4.2_with_ios_5_sdk/xcode_4.2_and_ios_5_sdk_for_snow_leopard.dmg) also run on Snow Leopard, but are only available to pay members 
+- [Xcode 4.6.3](https://developer.apple.com/devcenter/download.action?path=/Developer_Tools/xcode_4.6.3/xcode4630916281a.dmg) on OS X 10.7 (Lion)
+- [Xcode 5.1.1](https://developer.apple.com/devcenter/download.action?path=/Developer_Tools/xcode_5.1.1/xcode_5.1.1.dmg) on OS X 10.8 (Mountain Lion)
+- [Xcode 6.2](https://developer.apple.com/devcenter/download.action?path=/Developer_Tools/Xcode_6.2/Xcode_6.2.dmg) on OS X 10.9 (Mavericks)
+- [Xcode 7.2.1](https://developer.apple.com/devcenter/download.action?path=/Developer_Tools/Xcode_7.2.1/Xcode_7.2.1.dmg) on OS X 10.10 (Yosemite) and OS X 10.11 (El Capitan)
 
 More information about the compilers included in each version of Xcode can be found on the [MacPorts Wiki](https://trac.macports.org/wiki/XcodeVersionInfo).