如何判斷pkg-config軟件包所在的Cabal？

Question

Cabal無法安裝ffmpeg-light。它給人的錯誤：

cabal: The pkg-config package libavutil is required but it could not be found. 
Failed to install ffmpeg-light-0.7.1.1 
cabal: Error: some packages failed to install: 
ffmpeg-light-0.7.1.1 failed during the configure step. The exception was: 
ExitFailure 1 

的pkg配置包位於：

/home/timothy/ffmpeg_build/lib/pkgconfig 

我如何告訴卡瓦爾在哪裏看？

Answer 1

PKG_CONFIG_PATH變量告訴系統在哪裏尋找pkg-config軟件包。可以通過以下方式進行設置：export PKG_CONFIG_PATH =/pkg-config-directory。在本例中：

export PKG_CONFIG_PATH=/home/timothy/ffmpeg_build/lib/pkgconfig