Compilare: user.c: In function ‘main’: user.c:84:6: warning: implicit declaration of function ‘isdigit’ [-Wimplicit-function-declaration] if (isdigit (p1[i]) != 0) ^ user.c:8:9: warning: unused variable ‘ok’ [-Wunused-variable] int i, ok, len; ^ user.c:7:44: warning: unused variable ‘tok3’ [-Wunused-variable] char *p, *p1, *p2, *p3, **tok1, **tok2, **tok3, *copyp; ^ user.c:7:36: warning: unused variable ‘tok2’ [-Wunused-variable] char *p, *p1, *p2, *p3, **tok1, **tok2, **tok3, *copyp; ^ user.c:7:28: warning: unused variable ‘tok1’ [-Wunused-variable] char *p, *p1, *p2, *p3, **tok1, **tok2, **tok3, *copyp; ^ user.c:7:22: warning: unused variable ‘p3’ [-Wunused-variable] char *p, *p1, *p2, *p3, **tok1, **tok2, **tok3, *copyp; ^