dylibtree

dylibtree is a tool for inspecting the dynamic dependencies of a Mach-O binary recursively. It can be useful to understand what library loads another library that you may not expect. If it helps you can think of dylibtree as a recursive otool -L, or as a Mach-O version of lddtree.

Usage

To list all recursive dynamic dependencies, just pass a binary:

$ dylibtree /usr/bin/xcrun
/usr/bin/xcrun:
  /usr/lib/libxcselect.dylib:
    /usr/lib/libSystem.B.dylib:
      /usr/lib/system/libcache.dylib:
        /usr/lib/system/libsystem_malloc.dylib:
          /usr/lib/system/libcompiler_rt.dylib:
            /usr/lib/system/libunwind.dylib:
              /usr/lib/system/libsystem_malloc.dylib
...

You can limit the depth (and in turn the output) with --depth N:

$ dylibtree /usr/bin/xcrun --depth 2
/usr/bin/xcrun:
  /usr/lib/libxcselect.dylib:
    /usr/lib/libSystem.B.dylib:
  /usr/lib/libSystem.B.dylib

You can also exclude various prefixes depending on what you're investigating with --ignore-prefix:

$ dylibtree /Applications/Xcode.app/Contents/Applications/Instruments.app/Contents/MacOS/Instruments --ignore-prefix /usr/lib --ignore-prefix /System/Library
/Applications/Xcode.app/Contents/Applications/Instruments.app/Contents/MacOS/Instruments:
  @rpath/DVTInstrumentsUtilities.framework/Versions/A/DVTInstrumentsUtilities:
  @rpath/DVTInstrumentsFoundation.framework/Versions/A/DVTInstrumentsFoundation:
    @rpath/CoreSymbolicationDT.framework/Versions/A/CoreSymbolicationDT:
...

Installation

brew install keith/formulae/dylibtree

Implementation notes

• dylibtree uses the dyld shared cache, or other platform's runtime roots to discover dylibs. If you want to run dylibtree on a binary for a non macOS platform you must have that platform installed in Xcode, and must have built to a device with that platform to populate the symbols.
• dylibtree looks up the current locations for the runtime root for a platform, that can change over time, or you might download one manually that you want to use instead. If so you can pass --runtime-root or --shared-cache-path to override the default discovery. If the location has changed please submit an issue or PR so we can update it for everyone.
• dyld shared cache extraction uses Xcode's internal library, which means your currently selected Xcode version must support any shared caches being extracted. If you're on a beta version you'll likely need to have a beta Xcode selected (or set with DEVELOPER_DIR).