configure_file
: Copy a file to another location and modify its contents.configure_file(<input> <output>
[COPYONLY] [ESCAPE_QUOTES] [@ONLY])
Copies a file <input> to file <output> and substitutes variable values referenced in the file content. If <input> is a relative path it is evaluated with respect to the current source directory. The <input> must be a file, not a directory. If <output> is a relative path it is evaluated with respect to the current binary directory. If <output> names an existing directory the input file is placed in that directory with its original name.
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 replaces and ${VAR} will be ignored. This is useful for configuring scripts that use ${VAR}. Any occurrences of #cmakedefine VAR will be replaced with either #define VAR or /* #undef VAR */ depending on the setting of VAR in CMake. Any occurrences of #cmakedefine01 VAR will be replaced with either #define VAR 1 or #define VAR 0 depending on whether VAR evaluates to TRUE or FALSE in CMake