These procedures may be used to disassemble and reassemble file paths in a platform independent manner: they provide C-level access to the same functionality as the file split, file join, and file pathtype commands.
Tcl_SplitPath breaks a path into its constituent elements, returning an array of pointers to the elements using argcPtr and argvPtr. The area of memory pointed to by *argvPtr is dynamically allocated; in addition to the array of pointers, it also holds copies of all the path elements. It is the caller's responsibility to free all of this storage. For example, suppose that you have called Tcl_SplitPath with the following code:
int argc; char *path; char **argv; ... Tcl_SplitPath(string, &argc, &argv);
Then you should eventually free the storage with a call like the following:
Tcl_Free((char *) argv);
Tcl_JoinPath is the inverse of Tcl_SplitPath: it takes a collection of path elements given by argc and argv and generates a result string that is a properly constructed path. The result string is appended to resultPtr. ResultPtr must refer to an initialized Tcl_DString.
If the result of Tcl_SplitPath is passed to Tcl_JoinPath, the result will refer to the same location, but may not be in the same form. This is because Tcl_SplitPath and Tcl_JoinPath eliminate duplicate path separators and return a normalized form for each platform.
Tcl_GetPathType returns the type of the specified path, where Tcl_PathType is one of TCL_PATH_ABSOLUTE, TCL_PATH_RELATIVE, or TCL_PATH_VOLUME_RELATIVE. See the filename manual entry for a description of the path types for each platform.