/in/foo.c: In function 'main':
/in/foo.c:7:4: error: 'reyurn' undeclared (first use in this function)
    reyurn 0:
    ^~~~~~
/in/foo.c:7:4: note: each undeclared identifier is reported only once for each function it appears in
/in/foo.c:7:11: error: expected ';' before numeric constant
    reyurn 0:
           ^