1Protocol Buffers - Google's data interchange format 2=================================================== 3 4Copyright 2008 Google Inc. 5 6https://developers.google.com/protocol-buffers/ 7 8C++ Installation - Unix 9----------------------- 10 11If you get the source from github, you need to generate the configure script 12first: 13 14 $ ./autogen.sh 15 16This will download gtest source (which is used for C++ Protocol Buffer 17unit-tests) to the current directory and run automake, autoconf, etc. 18to generate the configure script and various template makefiles. 19 20You can skip this step if you are using a release package (which already 21contains gtest and the configure script). 22 23To build and install the C++ Protocol Buffer runtime and the Protocol 24Buffer compiler (protoc) execute the following: 25 26 $ ./configure 27 $ make 28 $ make check 29 $ make install 30 31If "make check" fails, you can still install, but it is likely that 32some features of this library will not work correctly on your system. 33Proceed at your own risk. 34 35"make install" may require superuser privileges. 36 37For advanced usage information on configure and make, see INSTALL.txt. 38 39**Hint on install location** 40 41 By default, the package will be installed to /usr/local. However, 42 on many platforms, /usr/local/lib is not part of LD_LIBRARY_PATH. 43 You can add it, but it may be easier to just install to /usr 44 instead. To do this, invoke configure as follows: 45 46 ./configure --prefix=/usr 47 48 If you already built the package with a different prefix, make sure 49 to run "make clean" before building again. 50 51**Compiling dependent packages** 52 53 To compile a package that uses Protocol Buffers, you need to pass 54 various flags to your compiler and linker. As of version 2.2.0, 55 Protocol Buffers integrates with pkg-config to manage this. If you 56 have pkg-config installed, then you can invoke it to get a list of 57 flags like so: 58 59 pkg-config --cflags protobuf # print compiler flags 60 pkg-config --libs protobuf # print linker flags 61 pkg-config --cflags --libs protobuf # print both 62 63 For example: 64 65 c++ my_program.cc my_proto.pb.cc `pkg-config --cflags --libs protobuf` 66 67 Note that packages written prior to the 2.2.0 release of Protocol 68 Buffers may not yet integrate with pkg-config to get flags, and may 69 not pass the correct set of flags to correctly link against 70 libprotobuf. If the package in question uses autoconf, you can 71 often fix the problem by invoking its configure script like: 72 73 configure CXXFLAGS="$(pkg-config --cflags protobuf)" \ 74 LIBS="$(pkg-config --libs protobuf)" 75 76 This will force it to use the correct flags. 77 78 If you are writing an autoconf-based package that uses Protocol 79 Buffers, you should probably use the PKG_CHECK_MODULES macro in your 80 configure script like: 81 82 PKG_CHECK_MODULES([protobuf], [protobuf]) 83 84 See the pkg-config man page for more info. 85 86 If you only want protobuf-lite, substitute "protobuf-lite" in place 87 of "protobuf" in these examples. 88 89**Note for cross-compiling** 90 91 The makefiles normally invoke the protoc executable that they just 92 built in order to build tests. When cross-compiling, the protoc 93 executable may not be executable on the host machine. In this case, 94 you must build a copy of protoc for the host machine first, then use 95 the --with-protoc option to tell configure to use it instead. For 96 example: 97 98 ./configure --with-protoc=protoc 99 100 This will use the installed protoc (found in your $PATH) instead of 101 trying to execute the one built during the build process. You can 102 also use an executable that hasn't been installed. For example, if 103 you built the protobuf package for your host machine in ../host, 104 you might do: 105 106 ./configure --with-protoc=../host/src/protoc 107 108 Either way, you must make sure that the protoc executable you use 109 has the same version as the protobuf source code you are trying to 110 use it with. 111 112**Note for Solaris users** 113 114 Solaris 10 x86 has a bug that will make linking fail, complaining 115 about libstdc++.la being invalid. We have included a work-around 116 in this package. To use the work-around, run configure as follows: 117 118 ./configure LDFLAGS=-L$PWD/src/solaris 119 120 See src/solaris/libstdc++.la for more info on this bug. 121 122**Note for HP C++ Tru64 users** 123 124 To compile invoke configure as follows: 125 126 ./configure CXXFLAGS="-O -std ansi -ieee -D__USE_STD_IOSTREAM" 127 128 Also, you will need to use gmake instead of make. 129 130C++ Installation - Windows 131-------------------------- 132 133If you are using Microsoft Visual C++, see vsprojects/readme.txt. 134 135If you are using Cygwin or MinGW, follow the Unix installation 136instructions, above. 137 138Binary Compatibility Warning 139---------------------------- 140 141Due to the nature of C++, it is unlikely that any two versions of the 142Protocol Buffers C++ runtime libraries will have compatible ABIs. 143That is, if you linked an executable against an older version of 144libprotobuf, it is unlikely to work with a newer version without 145re-compiling. This problem, when it occurs, will normally be detected 146immediately on startup of your app. Still, you may want to consider 147using static linkage. You can configure this package to install 148static libraries only using: 149 150 ./configure --disable-shared 151 152Java and Python Installation 153---------------------------- 154 155The Java and Python runtime libraries for Protocol Buffers are located 156in the java and python directories. See the README file in each 157directory for more information on how to compile and install them. 158Note that both of them require you to first install the Protocol 159Buffer compiler (protoc), which is part of the C++ package. 160 161Usage 162----- 163 164The complete documentation for Protocol Buffers is available via the 165web at: 166 167 https://developers.google.com/protocol-buffers/ 168