Using gcc 4.0.2 on AIX 5.3: $ cat a.cxx #include <iostream> $ g++ -D_LARGE_FILES=1 -c a.cxx /opt/TWWfsw/gcc402/include/c++/cstdio:108: error: '::fgetpos' has not been declared /opt/TWWfsw/gcc402/include/c++/cstdio:110: error: '::fopen' has not been declared /opt/TWWfsw/gcc402/include/c++/cstdio:115: error: '::freopen' has not been declared /opt/TWWfsw/gcc402/include/c++/cstdio:118: error: '::fsetpos' has not been declared Compiling without -D_LARGE_FILES=1 works but why does building with -D_LARGE_FILES=1 cause a problem? Maybe because of the following in <stdio.h>: #ifdef _LARGE_FILES #define fseeko fseeko64 #define ftello ftello64 #define fgetpos fgetpos64 #define fsetpos fsetpos64 #define fopen fopen64 #define freopen freopen64 #endif /* _LARGE_FILES */ -- albert chin (china@xxxxxxxxxxxxxxxxxx)