我怎么知道仅查看目标系统根目录？

How can I tell it to look in the target sysroot only?

有一系列CMake变量 CMAKE_FIND_ROOT_PATH_MODE _ * ，可针对不同的CMake命令调整搜索策略：

There is a family of CMake variables CMAKE_FIND_ROOT_PATH_MODE_*, which adjusts search strategy for different CMake commands:

• BOTH 值意味着搜索 target 和 host （构建）路径。当未设置变量时，这也是默认行为。

• BOTH value means that both target and host (build) paths are searched. This is also a default behavior, when a variable is not set.

ONLY 值表示仅 target

ONLY value means that only target is searched.

Never 值表示只搜索主机。

变量列表：

• CMAKE_FIND_ROOT_PATH_MODE_LIBRARY 影响 find_library（）调用

CMAKE_FIND_ROOT_PATH_MODE_INCLUDE 对 find_path（）和 find_file（）调用

CMAKE_FIND_ROOT_PATH_MODE_PACKAGE 影响 CONFIG 中的 find_package（） >模式（搜索 * Config.cmake 文件时）。

CMAKE_FIND_ROOT_PATH_MODE_PACKAGE affects on find_package() in CONFIG mode (when *Config.cmake file is searched).

CMAKE_FIND_ROOT_PATH_MODE_PROGRAM 会影响 find_program（）

CMAKE_FIND_ROOT_PATH_MODE_PROGRAM affects on find_program() call.

通常，具体的 find_package（）调用可能会受到所有这些变量的影响。在搜索库的情况下，通常只设置其中三个即可：

Generally, concrete find_package() call may be affected by all of these variables. In case of searching libraries, it is usually suffificient to set only 3 of them:

# Search libraries only under *target* paths.
set(CMAKE_FIND_ROOT_PATH_MODE_LIBRARY ONLY)
set(CMAKE_FIND_ROOT_PATH_MODE_INCLUDE ONLY)
set(CMAKE_FIND_ROOT_PATH_MODE_PACKAGE ONLY)

$ b

变量 CMAKE_FIND_ROOT_PATH_MODE _ * 通常在工具链文件中设置。

Variables CMAKE_FIND_ROOT_PATH_MODE_* are normally set in toolchain files.