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Diffstat (limited to 'Help/command/file.rst')
| -rw-r--r-- | Help/command/file.rst | 315 |
1 files changed, 200 insertions, 115 deletions
diff --git a/Help/command/file.rst b/Help/command/file.rst index 5ce86e5..d4a6006 100644 --- a/Help/command/file.rst +++ b/Help/command/file.rst @@ -3,23 +3,44 @@ file File manipulation command. ------------------------------------------------------------------------------- +Synopsis +^^^^^^^^ -:: +.. parsed-literal:: - file(WRITE <filename> <content>...) - file(APPEND <filename> <content>...) + `Reading`_ + file(`READ`_ <filename> <out-var> [...]) + file(`STRINGS`_ <filename> <out-var> [...]) + file(`\<HASH\> <HASH_>`_ <filename> <out-var>) + file(`TIMESTAMP`_ <filename> <out-var> [...]) -Write ``<content>`` into a file called ``<filename>``. If the file does -not exist, it will be created. If the file already exists, ``WRITE`` -mode will overwrite it and ``APPEND`` mode will append to the end. -Any directories in the path specified by ``<filename>`` that do not -exist will be created. + `Writing`_ + file({`WRITE`_ | `APPEND`_} <filename> <content>...) + file({`TOUCH`_ | `TOUCH_NOCREATE`_} [<file>...]) + file(`GENERATE`_ OUTPUT <output-file> [...]) -If the file is a build input, use the :command:`configure_file` command -to update the file only when its content changes. + `Filesystem`_ + file({`GLOB`_ | `GLOB_RECURSE`_} <out-var> [...] [<globbing-expr>...]) + file(`RENAME`_ <oldname> <newname>) + file({`REMOVE`_ | `REMOVE_RECURSE`_ } [<files>...]) + file(`MAKE_DIRECTORY`_ [<dir>...]) + file({`COPY`_ | `INSTALL`_} <file>... DESTINATION <dir> [...]) + + `Path Conversion`_ + file(`RELATIVE_PATH`_ <out-var> <directory> <file>) + file({`TO_CMAKE_PATH`_ | `TO_NATIVE_PATH`_} <path> <out-var>) + + `Transfer`_ + file(`DOWNLOAD`_ <url> <file> [...]) + file(`UPLOAD`_ <file> <url> [...]) + + `Locking`_ + file(`LOCK`_ <path> [...]) + +Reading +^^^^^^^ ------------------------------------------------------------------------------- +.. _READ: :: @@ -31,7 +52,7 @@ Read content from a file called ``<filename>`` and store it in a read at most ``<max-in>`` bytes. The ``HEX`` option causes data to be converted to a hexadecimal representation (useful for binary data). ------------------------------------------------------------------------------- +.. _STRINGS: :: @@ -82,7 +103,7 @@ For example, the code stores a list in the variable ``myfile`` in which each item is a line from the input file. ------------------------------------------------------------------------------- +.. _HASH: :: @@ -93,15 +114,116 @@ store it in a ``<variable>``. The supported ``<HASH>`` algorithm names are those listed by the :ref:`string(\<HASH\>) <Supported Hash Algorithms>` command. ------------------------------------------------------------------------------- +.. _TIMESTAMP: + +:: + + file(TIMESTAMP <filename> <variable> [<format>] [UTC]) + +Compute a string representation of the modification time of ``<filename>`` +and store it in ``<variable>``. Should the command be unable to obtain a +timestamp variable will be set to the empty string (""). + +See the :command:`string(TIMESTAMP)` command for documentation of +the ``<format>`` and ``UTC`` options. + +Writing +^^^^^^^ + +.. _WRITE: +.. _APPEND: + +:: + + file(WRITE <filename> <content>...) + file(APPEND <filename> <content>...) + +Write ``<content>`` into a file called ``<filename>``. If the file does +not exist, it will be created. If the file already exists, ``WRITE`` +mode will overwrite it and ``APPEND`` mode will append to the end. +Any directories in the path specified by ``<filename>`` that do not +exist will be created. + +If the file is a build input, use the :command:`configure_file` command +to update the file only when its content changes. + +.. _TOUCH: +.. _TOUCH_NOCREATE: + +:: + + file(TOUCH [<files>...]) + file(TOUCH_NOCREATE [<files>...]) + +Create a file with no content if it does not yet exist. If the file already +exists, its access and/or modification will be updated to the time when the +function call is executed. + +Use TOUCH_NOCREATE to touch a file if it exists but not create it. If a file +does not exist it will be silently ignored. + +With TOUCH and TOUCH_NOCREATE the contents of an existing file will not be +modified. + +.. _GENERATE: + +:: + + file(GENERATE OUTPUT output-file + <INPUT input-file|CONTENT content> + [CONDITION expression]) + +Generate an output file for each build configuration supported by the current +:manual:`CMake Generator <cmake-generators(7)>`. Evaluate +:manual:`generator expressions <cmake-generator-expressions(7)>` +from the input content to produce the output content. The options are: + +``CONDITION <condition>`` + Generate the output file for a particular configuration only if + the condition is true. The condition must be either ``0`` or ``1`` + after evaluating generator expressions. + +``CONTENT <content>`` + Use the content given explicitly as input. + +``INPUT <input-file>`` + Use the content from a given file as input. + A relative path is treated with respect to the value of + :variable:`CMAKE_CURRENT_SOURCE_DIR`. See policy :policy:`CMP0070`. + +``OUTPUT <output-file>`` + Specify the output file name to generate. Use generator expressions + such as ``$<CONFIG>`` to specify a configuration-specific output file + name. Multiple configurations may generate the same output file only + if the generated content is identical. Otherwise, the ``<output-file>`` + must evaluate to an unique name for each configuration. + A relative path (after evaluating generator expressions) is treated + with respect to the value of :variable:`CMAKE_CURRENT_BINARY_DIR`. + See policy :policy:`CMP0070`. + +Exactly one ``CONTENT`` or ``INPUT`` option must be given. A specific +``OUTPUT`` file may be named by at most one invocation of ``file(GENERATE)``. +Generated files are modified and their timestamp updated on subsequent cmake +runs only if their content is changed. + +Note also that ``file(GENERATE)`` does not create the output file until the +generation phase. The output file will not yet have been written when the +``file(GENERATE)`` command returns, it is written only after processing all +of a project's ``CMakeLists.txt`` files. + +Filesystem +^^^^^^^^^^ + +.. _GLOB: +.. _GLOB_RECURSE: :: file(GLOB <variable> - [LIST_DIRECTORIES true|false] [RELATIVE <path>] + [LIST_DIRECTORIES true|false] [RELATIVE <path>] [CONFIGURE_DEPENDS] [<globbing-expressions>...]) file(GLOB_RECURSE <variable> [FOLLOW_SYMLINKS] - [LIST_DIRECTORIES true|false] [RELATIVE <path>] + [LIST_DIRECTORIES true|false] [RELATIVE <path>] [CONFIGURE_DEPENDS] [<globbing-expressions>...]) Generate a list of files that match the ``<globbing-expressions>`` and @@ -110,6 +232,11 @@ regular expressions, but much simpler. If ``RELATIVE`` flag is specified, the results will be returned as relative paths to the given path. The results will be ordered lexicographically. +If the ``CONFIGURE_DEPENDS`` flag is specified, CMake will add logic +to the main build system check target to rerun the flagged ``GLOB`` commands +at build time. If any of the outputs change, CMake will regenerate the build +system. + By default ``GLOB`` lists directories - directories are omitted in result if ``LIST_DIRECTORIES`` is set to false. @@ -118,6 +245,10 @@ By default ``GLOB`` lists directories - directories are omitted in result if your source tree. If no CMakeLists.txt file changes when a source is added or removed then the generated build system cannot know when to ask CMake to regenerate. + The ``CONFIGURE_DEPENDS`` flag may not work reliably on all generators, or if + a new generator is added in the future that cannot support it, projects using + it will be stuck. Even if ``CONFIGURE_DEPENDS`` works reliably, there is + still a cost to perform the check on every rebuild. Examples of globbing expressions include:: @@ -139,7 +270,7 @@ Examples of recursive globbing include:: /dir/*.py - match all python files in /dir and subdirectories ------------------------------------------------------------------------------- +.. _RENAME: :: @@ -148,7 +279,8 @@ Examples of recursive globbing include:: Move a file or directory within a filesystem from ``<oldname>`` to ``<newname>``, replacing the destination atomically. ------------------------------------------------------------------------------- +.. _REMOVE: +.. _REMOVE_RECURSE: :: @@ -159,7 +291,7 @@ Remove the given files. The ``REMOVE_RECURSE`` mode will remove the given files and directories, also non-empty directories. No error is emitted if a given file does not exist. ------------------------------------------------------------------------------- +.. _MAKE_DIRECTORY: :: @@ -167,7 +299,44 @@ given file does not exist. Create the given directories and their parents as needed. ------------------------------------------------------------------------------- +.. _COPY: +.. _INSTALL: + +:: + + file(<COPY|INSTALL> <files>... DESTINATION <dir> + [FILE_PERMISSIONS <permissions>...] + [DIRECTORY_PERMISSIONS <permissions>...] + [NO_SOURCE_PERMISSIONS] [USE_SOURCE_PERMISSIONS] + [FILES_MATCHING] + [[PATTERN <pattern> | REGEX <regex>] + [EXCLUDE] [PERMISSIONS <permissions>...]] [...]) + +The ``COPY`` signature copies files, directories, and symlinks to a +destination folder. Relative input paths are evaluated with respect +to the current source directory, and a relative destination is +evaluated with respect to the current build directory. Copying +preserves input file timestamps, and optimizes out a file if it exists +at the destination with the same timestamp. Copying preserves input +permissions unless explicit permissions or ``NO_SOURCE_PERMISSIONS`` +are given (default is ``USE_SOURCE_PERMISSIONS``). + +See the :command:`install(DIRECTORY)` command for documentation of +permissions, ``FILES_MATCHING``, ``PATTERN``, ``REGEX``, and +``EXCLUDE`` options. Copying directories preserves the structure +of their content even if options are used to select a subset of +files. + +The ``INSTALL`` signature differs slightly from ``COPY``: it prints +status messages (subject to the :variable:`CMAKE_INSTALL_MESSAGE` variable), +and ``NO_SOURCE_PERMISSIONS`` is default. +Installation scripts generated by the :command:`install` command +use this signature (with some undocumented options for internal use). + +Path Conversion +^^^^^^^^^^^^^^^ + +.. _RELATIVE_PATH: :: @@ -176,7 +345,8 @@ Create the given directories and their parents as needed. Compute the relative path from a ``<directory>`` to a ``<file>`` and store it in the ``<variable>``. ------------------------------------------------------------------------------- +.. _TO_CMAKE_PATH: +.. _TO_NATIVE_PATH: :: @@ -194,7 +364,11 @@ path with platform-specific slashes (``\`` on Windows and ``/`` elsewhere). Always use double quotes around the ``<path>`` to be sure it is treated as a single argument to this command. ------------------------------------------------------------------------------- +Transfer +^^^^^^^^ + +.. _DOWNLOAD: +.. _UPLOAD: :: @@ -281,99 +455,10 @@ check certificates and/or use ``EXPECTED_HASH`` to verify downloaded content. If neither ``TLS`` option is given CMake will check variables ``CMAKE_TLS_VERIFY`` and ``CMAKE_TLS_CAINFO``, respectively. ------------------------------------------------------------------------------- - -:: - - file(TIMESTAMP <filename> <variable> [<format>] [UTC]) - -Compute a string representation of the modification time of ``<filename>`` -and store it in ``<variable>``. Should the command be unable to obtain a -timestamp variable will be set to the empty string (""). - -See the :command:`string(TIMESTAMP)` command for documentation of -the ``<format>`` and ``UTC`` options. - ------------------------------------------------------------------------------- - -:: - - file(GENERATE OUTPUT output-file - <INPUT input-file|CONTENT content> - [CONDITION expression]) - -Generate an output file for each build configuration supported by the current -:manual:`CMake Generator <cmake-generators(7)>`. Evaluate -:manual:`generator expressions <cmake-generator-expressions(7)>` -from the input content to produce the output content. The options are: - -``CONDITION <condition>`` - Generate the output file for a particular configuration only if - the condition is true. The condition must be either ``0`` or ``1`` - after evaluating generator expressions. - -``CONTENT <content>`` - Use the content given explicitly as input. - -``INPUT <input-file>`` - Use the content from a given file as input. - A relative path is treated with respect to the value of - :variable:`CMAKE_CURRENT_SOURCE_DIR`. See policy :policy:`CMP0070`. - -``OUTPUT <output-file>`` - Specify the output file name to generate. Use generator expressions - such as ``$<CONFIG>`` to specify a configuration-specific output file - name. Multiple configurations may generate the same output file only - if the generated content is identical. Otherwise, the ``<output-file>`` - must evaluate to an unique name for each configuration. - A relative path (after evaluating generator expressions) is treated - with respect to the value of :variable:`CMAKE_CURRENT_BINARY_DIR`. - See policy :policy:`CMP0070`. - -Exactly one ``CONTENT`` or ``INPUT`` option must be given. A specific -``OUTPUT`` file may be named by at most one invocation of ``file(GENERATE)``. -Generated files are modified and their timestamp updated on subsequent cmake -runs only if their content is changed. - -Note also that ``file(GENERATE)`` does not create the output file until the -generation phase. The output file will not yet have been written when the -``file(GENERATE)`` command returns, it is written only after processing all -of a project's ``CMakeLists.txt`` files. - ------------------------------------------------------------------------------- - -:: - - file(<COPY|INSTALL> <files>... DESTINATION <dir> - [FILE_PERMISSIONS <permissions>...] - [DIRECTORY_PERMISSIONS <permissions>...] - [NO_SOURCE_PERMISSIONS] [USE_SOURCE_PERMISSIONS] - [FILES_MATCHING] - [[PATTERN <pattern> | REGEX <regex>] - [EXCLUDE] [PERMISSIONS <permissions>...]] [...]) - -The ``COPY`` signature copies files, directories, and symlinks to a -destination folder. Relative input paths are evaluated with respect -to the current source directory, and a relative destination is -evaluated with respect to the current build directory. Copying -preserves input file timestamps, and optimizes out a file if it exists -at the destination with the same timestamp. Copying preserves input -permissions unless explicit permissions or ``NO_SOURCE_PERMISSIONS`` -are given (default is ``USE_SOURCE_PERMISSIONS``). - -See the :command:`install(DIRECTORY)` command for documentation of -permissions, ``FILES_MATCHING``, ``PATTERN``, ``REGEX``, and -``EXCLUDE`` options. Copying directories preserves the structure -of their content even if options are used to select a subset of -files. - -The ``INSTALL`` signature differs slightly from ``COPY``: it prints -status messages (subject to the :variable:`CMAKE_INSTALL_MESSAGE` variable), -and ``NO_SOURCE_PERMISSIONS`` is default. -Installation scripts generated by the :command:`install` command -use this signature (with some undocumented options for internal use). +Locking +^^^^^^^ ------------------------------------------------------------------------------- +.. _LOCK: :: |