rtrim

This function returns a string with whitespace (or other characters) stripped from the end of str.
rtrim ( string $str [, string $character_mask ] ) : string

Without the second parameter, rtrim() will strip these characters:

” ” (ASCII 32 (0x20)), an ordinary space.
“\t” (ASCII 9 (0x09)), a tab.
“\n” (ASCII 10 (0x0A)), a new line (line feed).
“\r” (ASCII 13 (0x0D)), a carriage return.
“\0” (ASCII 0 (0x00)), the NULL-byte.
“\x0B” (ASCII 11 (0x0B)), a vertical tab.