Determines whether or not the program is being run in a terminal (virtual TTY).
"isatty() returns 1 if fd is an open file descriptor referring to a terminal; otherwise 0 is returned, and errno is set to indicate the error."
true if the current environment appears to be a terminal; false if not (e.g. pager or certain IDEs with terminal windows).
See Implementation
Determines whether or not the program is being run in a terminal (virtual TTY).
"isatty() returns 1 if fd is an open file descriptor referring to a terminal; otherwise 0 is returned, and errno is set to indicate the error."