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author | Craig Scott <craig.scott@crascit.com> | 2019-02-16 08:32:52 (GMT) |
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committer | Craig Scott <craig.scott@crascit.com> | 2019-02-16 09:55:49 (GMT) |
commit | 0f5a9f7934913935d632fc596ba1b585aa10fa29 (patch) | |
tree | 70bcb53cfa80620cff0a7ea8b8a46971ecd74f6d /Help/command/file.rst | |
parent | e6897c72e7c59f7a0b82ed19c1bdb40d42f7adaa (diff) | |
download | CMake-0f5a9f7934913935d632fc596ba1b585aa10fa29.zip CMake-0f5a9f7934913935d632fc596ba1b585aa10fa29.tar.gz CMake-0f5a9f7934913935d632fc596ba1b585aa10fa29.tar.bz2 |
Help: Clarify and improve readability of link-related file subcommands
Diffstat (limited to 'Help/command/file.rst')
-rw-r--r-- | Help/command/file.rst | 46 |
1 files changed, 23 insertions, 23 deletions
diff --git a/Help/command/file.rst b/Help/command/file.rst index db4d6fc..465e567 100644 --- a/Help/command/file.rst +++ b/Help/command/file.rst @@ -26,8 +26,8 @@ Synopsis file(`MAKE_DIRECTORY`_ [<dir>...]) file({`COPY`_ | `INSTALL`_} <file>... DESTINATION <dir> [...]) file(`SIZE`_ <filename> <out-var>) - file(`READ_SYMLINK`_ <filename> <out-var>) - file(`CREATE_LINK`_ <file> <new-file> [...]) + file(`READ_SYMLINK`_ <linkname> <out-var>) + file(`CREATE_LINK`_ <original> <linkname> [...]) `Path Conversion`_ file(`RELATIVE_PATH`_ <out-var> <directory> <file>) @@ -350,22 +350,22 @@ pointing to a file and is readable. .. code-block:: cmake - file(READ_SYMLINK <filename> <variable>) + file(READ_SYMLINK <linkname> <variable>) -Read the symlink at ``<filename>`` and put the result in ``<variable>``. -Requires that ``<filename>`` is a valid path pointing to a symlink. If -``<filename>`` does not exist, or is not a symlink, an error is thrown. +This subcommand queries the symlink ``<linkname>`` and stores the path it +points to in the result ``<variable>``. If ``<linkname>`` does not exist or +is not a symlink, CMake issues a fatal error. Note that this command returns the raw symlink path and does not resolve -relative symlinks. If you want to resolve the relative symlink yourself, you -could do something like this: +a relative path. The following is an example of how to ensure that an +absolute path is obtained: .. code-block:: cmake - set(filename "/path/to/foo.sym") - file(READ_SYMLINK "${filename}" result) + set(linkname "/path/to/foo.sym") + file(READ_SYMLINK "${linkname}" result) if(NOT IS_ABSOLUTE "${result}") - get_filename_component(dir "${filename}" DIRECTORY) + get_filename_component(dir "${linkname}" DIRECTORY) set(result "${dir}/${result}") endif() @@ -373,23 +373,23 @@ could do something like this: .. code-block:: cmake - file(CREATE_LINK <file> <new-file> + file(CREATE_LINK <original> <linkname> [RESULT <result>] [COPY_ON_ERROR] [SYMBOLIC]) -Create a link to ``<file>`` at ``<new-file>``. +Create a link ``<linkname>`` that points to ``<original>``. +It will be a hard link by default, but providing the ``SYMBOLIC`` option +results in a symbolic link instead. Hard links require that ``original`` +exists and is a file, not a directory. If ``<linkname>`` already exists, +it will be overwritten. -It is a hard link by default. This can be changed to symbolic links by -using ``SYMBOLIC``. The original file needs to exist for hard links. - -The ``<result>`` variable, if specified, gets the status of the operation. -It is set to ``0`` in case of success. Otherwise, it contains the error -generated. In case of failures, if ``RESULT`` is not specified, a fatal error -is emitted. +The ``<result>`` variable, if specified, receives the status of the operation. +It is set to ``0`` upon success or an error message otherwise. If ``RESULT`` +is not specified and the operation fails, a fatal error is emitted. Specifying ``COPY_ON_ERROR`` enables copying the file as a fallback if -creating the link fails. - -Overwrites the ``<new-file>`` if it exists. +creating the link fails. It can be useful for handling situations such as +``<original>`` and ``<linkname>`` being on different drives or mount points, +which would make them unable to support a hard link. Path Conversion ^^^^^^^^^^^^^^^ |