Is there an equivalent of the C function mbsinvalid on Linux?

Porting a C application from AIX to Linux - does anyone know if there's an equivalent of the mbsinvalid() function on Linux?

From the AIX pages:

"The mbsinvalid subroutine examines the string pointed to by the S parameter to determine the validity of characters. The LC_CTYPE category affects the behavior of the mbsinvalid subroutine."

http://publib.boulder.ibm.com/infocenter/pseries/v5r3/index.jsp?topic=/com.ibm.aix.basetechref/doc/basetrf1/mbsinvalid.htm

Thanks!