filegdb2shp

1) Get the FileGDB API http://www.esri.com/apps/products/download/

2) Extract it somewhere on your system and remember the path :)

3) Do:
> mkdir build   #directory where we are playing around
> cd build
> git clone https://github.com/OSGeo/gdal.git
> cd gdal
> ./configure --with-fgdb=/path/to/your/FileGDB_API
> make  # this will take a while ....
# (make install)  # optional, I'm just using it locally

*** Note: you will need all the dependencies, development files as well as all the compile tools _before_ configuring and compiling geo. I don't dig into this topic here, but if somebody has trouble, I might be able to help. ***

4) First test:
build/gdal/apps/ogrinfo --formats   # I have to use absolute paths, since I didn't install gdal system wide

- If you are lucky you will see a output like this:

Supported Formats:
...
-> "FileGDB" (read/write)
...

5) Now you can use ogrinfo or ogr2ogr to access your FileGDB

> build/gdal/apps/ogrinfo /path/to/your/database.gdb <layername> -summary

* Convert a FileGDB to Shapefile:

> build/gdal/apps/ogr2ogr -f "ESRI Shapefile" <out_directory> /path/to/your/database.gdb

--> A directory will be created and for each layer within the filegdb a shapefile set will be created.

* You could also use a query to retrieve a subset of your filegdb. There is an example on the gdal site http://www.gdal.org/ogrinfo.html

This is OK, but there is an easier way to install as a homebrewed gdal plug-in

1. Get the FileGDB API http://www.esri.com/apps/products/download/ # same as above
2. Extract it somewhere on your system and record the path (homebrew will require its /Library/Caches/Homebrew) # same as above
3. Do:

mv ~/Downloads/FileGDB_API_1_3-64.zip /Library/Caches/Homebrew
export GDAL_THIRD_PARTY=/Library/Caches/Homebrew
brew install gdal-filegdb
export GDAL_DRIVER_PATH=/usr/local/lib/gdalplugins
4) Check that FileGDB API is plugged in:
ogrinfo --formats
Supported Formats:
-> "FileGDB" (read/write)
5) Test it:

• download a test file, e.g.:
  http://trac.osgeo.org/gdal/raw-attachment/wiki/FileGDB/test_fgdb.gdb.zip
• run:
  ogr2ogr -f "ESRI Shapefile" /destination/path /path/to/test_fgdb.gdb.zip

==> You should end up with several files output, including the .shp (ESRI shapefile(s))

Note: The ESRI FileGDB API only converts ESRI v. 10+ .gdb's. May want to consider using OpenFileGDB instead for vv. 9.+.
http://www.gdal.org/drv_openfilegdb.html