Compilare: main.cpp: In function 'void Clear()': main.cpp:33:22: warning: converting to non-pointer type 'char' from NULL [-Wconversion-null] canvas[i][M+1]=NULL; ^~~~ main.cpp: In function 'bool Run_command(FILE*, FILE*)': main.cpp:141:30: warning: converting to non-pointer type 'char' from NULL [-Wconversion-null] name[strlen(name)-1]=NULL; ^~~~ main.cpp:109:27: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] fscanf(in,"%c ",&command); ^ main.cpp:122:35: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] fscanf(in,"%d ",&args[i]); ^ main.cpp:139:33: warning: ignoring return value of 'char* fgets(char*, int, FILE*)', declared with attribute warn_unused_result [-Wunused-result] fgets(name,strlen(name),in); ^