get_filename_component

Get a specific component of a full filename.

Changed in version 3.20: This command has been superseded by the cmake_path() command, except for REALPATH, which is now offered by file(REAL_PATH), and PROGRAM, now available in separate_arguments(PROGRAM).

Changed in version 3.24: The undocumented feature offering the capability to query the Windows registry is superseded by cmake_host_system_information(QUERY WINDOWS_REGISTRY) command.

get_filename_component(<var> <FileName> <mode> [CACHE])

Sets <var> to a component of <FileName>, where <mode> is one of:

  • DIRECTORY - directory without file name.

  • NAME - file name without directory.

  • EXT - file name longest extension (.b.c from d/a.b.c).

  • NAME_WE - file name with neither the directory nor the longest extension.

  • LAST_EXT - file name last extension (.c from d/a.b.c).

  • NAME_WLE - file name with neither the directory nor the last extension.

  • PATH - legacy alias for DIRECTORY (use for CMake <= 2.8.11).

Added in version 3.14: Added the LAST_EXT and NAME_WLE modes.

Paths are returned with forward slashes and have no trailing slashes. If the optional CACHE argument is specified, the result variable is added to the cache.

get_filename_component(<var> <FileName> <mode> [BASE_DIR <dir>] [CACHE])

Added in version 3.4.

Sets <var> to the absolute path of <FileName>, where <mode> is one of:

  • ABSOLUTE - full path to file.

  • REALPATH - full path to existing file with symlinks resolved.

If the provided <FileName> is a relative path, it is evaluated relative to the given base directory <dir>. If no base directory is provided, the default base directory will be CMAKE_CURRENT_SOURCE_DIR.

Paths are returned with forward slashes and have no trailing slashes. If the optional CACHE argument is specified, the result variable is added to the cache.

get_filename_component(<var> <FileName> PROGRAM [PROGRAM_ARGS <arg_var>] [CACHE])

The program in <FileName> will be found in the system search path or left as a full path. If PROGRAM_ARGS is present with PROGRAM, then any command-line arguments present in the <FileName> string are split from the program name and stored in <arg_var>. This is used to separate a program name from its arguments in a command line string.

See Also