char Tcl_Backslash(src, countPtr)
The use of Tcl_Backslash is deprecated in favor of Tcl_UtfBackslash.
This is a utility procedure provided for backwards compatibility with non-internationalized Tcl extensions. It parses a backslash sequence and returns the low byte of the Unicode character corresponding to the sequence. Tcl_Backslash modifies *countPtr to contain the number of characters in the backslash sequence.
See the Tcl manual entry for information on the valid backslash sequences. All of the sequences described in the Tcl manual entry are supported by Tcl_Backslash.