Problem 59 GCC密切相关的一些环境变量？

Problem59 GCC密切相关的一些环境变量？

Ans:

环境变量	描述
TMPDIR	Thisvariable shows location of temporary file location. GCC uses　thislocation to store temporary files during the compilingand　linking processes.
GCC_EXEC_PREFIX	If thisvariable is set, GCC will look into the directory to findsub　programs.
COMPILER_PATH	Thisis a colon-separated list of directories that GCC uses to find out subprograms if search fails using GCC_EXEC_PREFIX variable.
LIBRARY_PATH	Thisis a colon-separated list of directories that is used to find out librariesfor linking process.
C_INCLUDE_PATH	Colonseparated list of directories to find out header files forC　programs.
CPLUS_INCLUDE_PATH	Colonseparated list of directories to find out header files forC++　programs.
LD_LIBRARY_PATH	Path forshared libraries.

下面的命令用于查看gcc查找头文件的默认路径：

gcc-v -E -

要设置其他的路径，用如下命令：

exportC_INCLUDE_PATH=/opt