Cmake，链接一个外部（也可能是第三方，也可能是自己编译的）库

相当于设置VS工程里面的：

然后，为了链接成可执行文件，链接器就会到指定的目录寻找相应的库了。

以下时Demo:

cmake_minimum_required(VERSION 2.8)

#set(CMAKE_C_COMPILER "D:VS2008ReleaseVCinamd64")
#set(CMAKE_CXX_COMPILER "D:VS2008ReleaseVCinamd64")

PROJECT(CONVERT) 

add_definitions(-D_CONSOLE)
add_definitions(-D_LIB)

add_definitions(-D_VISUALC_)
add_definitions(-DNeedFunctionPrototypes)

include_directories(../)


#shang LINK_DIRECTORIES(../../build/lib)
LINK_DIRECTORIES(${CMAKE_BINARY_DIR}/lib)



set(SRC ${PROJECT_SOURCE_DIR}/convert.c)


add_executable(convert ${SRC})

set(IMAGEMAGICK_LIB CORE_wand CORE_magick CORE_wmf CORE_pixman CORE_ffi CORE_croco CORE_cairo CORE_webp CORE_ttf CORE_tiff CORE_png CORE_pango CORE_lqr  CORE_libxml CORE_librsvg CORE_lcms CORE_jp2 CORE_jbig CORE_glib CORE_filters CORE_coders CORE_jpeg CORE_bzlib CORE_zLib)
target_link_libraries(convert ${IMAGEMAGICK_LIB} urlmon.lib)

set(CompilerFlags
        CMAKE_CXX_FLAGS
        CMAKE_CXX_FLAGS_DEBUG
        CMAKE_CXX_FLAGS_RELEASE
        CMAKE_C_FLAGS
        CMAKE_C_FLAGS_DEBUG
        CMAKE_C_FLAGS_RELEASE
        )
foreach(CompilerFlag ${CompilerFlags})
  string(REPLACE "/MD" "/MT" ${CompilerFlag} "${${CompilerFlag}}")
  string(REPLACE "/Ob0" "" ${CompilerFlag} "${${CompilerFlag}}")
  string(REPLACE "/TC" "" ${CompilerFlag} "${${CompilerFlag}}")
endforeach()

Reference：

http://stackoverflow.com/questions/8774593/cmake-link-to-external-library