Hi,

as reported in Debian's bug:
http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=504952

exrdisplay does not compile with a snapshot (dated 20090129) of g++ 4.4, as the declaration of the sscanf() function is missing:

> g++ -DHAVE_CONFIG_H -I. -I. -I../config -I/usr/include/freetype2 -D_THREAD_SAFE -D_REENTRANT -I.. -DHAVE_CTL_INTERPRETER=0  -I/usr/include/OpenEXR -pthread   -pipe -g -O2 -g -Wall -O2 -c -o applyCtl.o applyCtl.cpp
> applyCtl.cpp: In function 'float displayVideoGamma()':
> applyCtl.cpp:91: error: 'sscanf' was not declared in this scope
> applyCtl.cpp: In function 'Imf::Chromaticities<unnamed>::displayChromaticities()':
> applyCtl.cpp:136: error: 'sscanf' was not declared in this scope
> make[2]: * [applyCtl.o] Error 1

The attached patch fixes the problem (it depends on the fix of #23012, though). Like in #23012, a similar problem should also happen for playexr/ctlToLut.cpp.