cmake Configure file
Introduction
configure_file is a CMake function for copying a file to another location and modify its contents. This function is very useful for generating configuration files with paths, custom variables, using a generic template.
Remarks
Copy a file to another location and modify its contents.
configure_file(<input> <output>
[COPYONLY] [ESCAPE_QUOTES] [@ONLY]
[NEWLINE_STYLE [UNIX|DOS|WIN32|LF|CRLF] ])
Copies a file to file and substitutes variable values referenced in the file content. If is a relative path it is evaluated with respect to the current source directory. The must be a file, not a directory. If is a relative path it is evaluated with respect to the current binary directory. If names an existing directory the input file is placed in that directory with its original name.
If the file is modified the build system will re-run CMake to re-configure the file and generate the build system again.
This command replaces any variables in the input file referenced as ${VAR} or @VAR@ with their values as determined by CMake. If a variable is not defined, it will be replaced with nothing. If COPYONLY is specified, then no variable expansion will take place. If ESCAPE_QUOTES is specified then any substituted quotes will be C-style escaped. The file will be configured with the current values of CMake variables. If @ONLY is specified, only variables of the form @VAR@ will be replaced and ${VAR} will be ignored. This is useful for configuring scripts that use ${VAR}.
Input file lines of the form “#cmakedefine VAR ...” will be replaced with either “#define VAR ...” or /* #undef VAR */ depending on whether VAR is set in CMake to any value not considered a false constant by the if() command. (Content of ”...”, if any, is processed as above.) Input file lines of the form “#cmakedefine01 VAR” will be replaced with either “#define VAR 1” or “#define VAR 0” similarly.
With NEWLINE_STYLE the line ending could be adjusted:
'UNIX' or 'LF' for \n, 'DOS', 'WIN32' or 'CRLF' for \r\n.
COPYONLY must not be used with NEWLINE_STYLE.
