The Arduino IDE requires that a sketch be located in a folder of the same name. When opening a file that does not meet this sketch/folder name matching requirement the Arduino IDE presents a dialog:
The file "esp8266mon-serial.ino" needs to be inside a sketch folder named "esp8266mon-serial".
Create this folder, move the file, and continue?
After clicking "OK" the Arduino IDE currently moves only the file esp8266mon-serial.ino to the new folder, leaving behind the other source files. This causes compilation of the sketch to fail:
ESP8266mini-sniff-master\serial\esp8266mon-serial\esp8266mon-serial.ino:13:23: fatal error: functions.h: No such file or directory
The Arduino IDE requires that a sketch be located in a folder of the same name. When opening a file that does not meet this sketch/folder name matching requirement the Arduino IDE presents a dialog:
After clicking "OK" the Arduino IDE currently moves only the file esp8266mon-serial.ino to the new folder, leaving behind the other source files. This causes compilation of the sketch to fail: