The GCC compilation prompts "Warning: Implicit declaration of function 'inet _ aton '"

Write a simple network in LinuxProgramThe inet_aton function is used. When GCC is used for compilation,-STD = c99 is added during compilation. The compilation is successful, but the error "Warning: Implicit declaration of function 'inet _ aton'" is returned '". Remove-STD = c99 and pass the compilation normally. No error is reported. Google once found that some C extensions provided by GCC conflict with standard C. When "-STD = c99" is used in GCC, GCC will disable conflicting extensions. If you want to use GCC extension for c99 and set "-STD = gnu99", no error will be reported during compilation.

Http://stackoverflow.com/questions/1783792/why-does-gcc-report-implicit-declaration-of-function-round