This library is for the GeoIP Legacy format (dat). To read the MaxMind DB format (mmdb) used by GeoIP2, please see libmaxminddb.

The GeoIP Legacy C library enables the user to find geographical and network information of an IP address. To use this library, you may download our free GeoLite Legacy Country or City databases. These are updated at the beginning of every month. The latest versions are available at:

http://dev.maxmind.com/geoip/legacy/geolite

We also offer commercial GeoIP Legacy databases with greater accuracy and additional network information. For more details, see:

https://www.maxmind.com/en/geolocation_landing

If you use GeoIP Legacy to block access from high risk countries, you may wish to use our proxy detection service to block access from known proxy servers to reduce fraud and abuse. For more details, see:

https://www.maxmind.com/en/proxy

To install, run:

./configure
make
make check
make install

If you are using a GitHub checkout, please run the bootstrap script first to set up the build environment.

The GeoIP Legacy C library relies on GNU make, not on BSD make

There are five options available:

• GEOIP_STANDARD - Read database from file system. This uses the least memory.
• GEOIP_MEMORY_CACHE - Load database into memory. Provides faster performance but uses more memory.
• GEOIP_CHECK_CACHE - Check for updated database. If database has been updated, reload file handle and/or memory cache.
• GEOIP_INDEX_CACHE - Cache only the the most frequently accessed index portion of the database, resulting in faster lookups than GEOIP_STANDARD, but less memory usage than GEOIP_MEMORY_CACHE. This is useful for larger databases such as GeoIP Legacy Organization and GeoIP Legacy City. Note: for GeoIP Legacy Country, Region and Netspeed databases, GEOIP_INDEX_CACHE is equivalent to GEOIP_MEMORY_CACHE.
• GEOIP_MMAP_CACHE - Load database into mmap shared memory. MMAP is not available for 32bit Windows.
• GEOIP_SILENCE - Disables diagnostic messages to stderr in the library; error conditions are detectable via the return values.

These options can be combined using bit operators. For example you can use both GEOIP_MEMORY_CACHE and GEOIP_CHECK_CACHE by calling:

GeoIP_open("/path/to/GeoIP.dat", GEOIP_MEMORY_CACHE | GEOIP_CHECK_CACHE);

By default, the city name is returned in iso-8859-1 charset. To obtain the city name in utf8 instead, run:

GeoIP_set_charset(gi, GEOIP_CHARSET_UTF8);

To get the netmask of the netblock of the last lookup, use GeoIP_last_netblock(gi).

See the following files for examples of how to use the API:

test/
     test-geoip.c
     test-geoip-region.c
     test-geoip-city.c
     test-geoip-isp.c
     test-geoip-org.c
     test-geoip-netspeed.c

The test-geoip.c program works with both the GeoLite Legacy and GeoIP Legacy Country databases. The test-geoip-city.c program works with both the GeoLite Legacy and GeoIP Legacy City databases. The other example programs require the paid databases available (https://www.maxmind.com/en/geolocation_landing).

MaxMind offers a service where you can have your database updated automically each week. For more details see:

http://www.maxmind.com/en/license_key

Patrick McManus provide a patch to enhance the lookup speed in MEMORY_CACHE mode. If you feel, that the current MEMORY_CACHE mode is to slow try the patch:

http://sourceforge.net/mailarchive/forum.php?forum_name=geoip-c-discuss&max_rows=25&style=nested&viewmonth=200803

Please find the latest version of the C API on GitHub:

https://github.com/maxmind/geoip-api-c

In case of trouble building from source with libtool or autotools, update the generated configuration files by running:

./bootstrap

or

autoreconf -vfi

or

aclocal && autoconf && automake --add-missing

The Windows build is not thread-safe in STANDARD mode because the pread is not thread-safe.

If you run into trouble building your application with GeoIP Legacy support, try adding -fms-extensions to your CFLAGS. If you use Solaris and the default C compiler, use -features=extensions instead. These options enable unnamed union support to fix problems like: improper member use: dma_code or 'GeoIPRecord' has no member named 'dma_code'.

Note that it is recommended that you use GNU make. Also, if you are using OpenBSD, this library requires OpenBSD 3.1 or greater.

If you get a "cannot load shared object file: No such file or directory" error, add the directory libGeoIP.so was installed to the /etc/ld.so.conf file and run ldconfig.

On Solaris, if you get a ld: fatal: relocations remain against allocatable but non-writable sections, try runnign:

make clean
./configure --disable-shared
make

If you get a ar : command not found error, make sure that ar is in your path. On Solaris, ar is typically found in /usr/ccs/bin

If you get a bad interpreter: No such file or directory error when running ./configure, make sure that there are no DOS returns in the configure script. To remove DOS returns, run perl -pi -e 's/\r//g' configure.

If gcc fails while consuming a large amount of memory, try compiling with CFLAGS=-O1 (or -O0) instead of the default -O2. It seems that some versions of gcc have a bug and consume 1 GB of memory when optimizing certain source files. It has been reported on gcc 3.3.1 and with gcc 4.2(.0). Thanks to Kai Schaetzl for the report.

If GEOIP_MMAP_CACHE doesn't work on a 64bit machine, try adding the flag MAP_32BIT to the mmap call.

If you get a passing argument 3 of 'gethostbyname_r' from incompatible pointer type error on AIX, untar a fresh copy of thie library and delete the following two lines from ./configure:

#define HAVE_GETHOSTBYNAME_R 1

#define GETHOSTBYNAME_R_RETURNS_INT 1

then save the configure script and build it as usual:

./configure
make
sudo make install

Please report all issues with this code using the [GitHub issue tracker] (https://github.com/maxmind/geoip-api-c/issues).

If you are having an issue with a MaxMind database that is not specific to this API, please [contact MaxMind support] (http://www.maxmind.com/en/support).

To contribute, please submit a pull request on GitHub.