Cygwin's default person interface is the bash shell operating within the mintty terminal emulator.[25] The DLL also implements pseudo terminal (pty) devices, and Cygwin ships with numerous terminal emulators which are according to them, which includes rxvt/urxvt and xterm. The Edition of GCC that comes with Cygwin has various extensions https://acgwin86307.blogozz.com/36205784/acgwin-options