another strace result:
writev(1, [{"LS\6\0\201\0\0\0", 8}, {"PHP Warning: fgets(): supplied "..., 121}], 2) = 129
writev(1, [{"LS\6\0\200\0\0\0", 8}, {"PHP Warning: feof(): supplied a"..., 120}], 2) = 128
writev(1, [{"LS\6\0\201\0\0\0", 8}, {"PHP Warning: fgets(): supplied "..., 121}]...