Compilare: main.c: In function 'main': main.c:9:2: warning: ignoring return value of 'freopen', declared with attribute warn_unused_result [-Wunused-result] freopen("strmatch.in", "r", stdin); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ main.c:10:2: warning: ignoring return value of 'freopen', declared with attribute warn_unused_result [-Wunused-result] freopen("strmatch.out", "w", stdout); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ main.c:13:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result] scanf("%s%s", pattern, string); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ main.c:87:2: warning: 'position' may be used uninitialized in this function [-Wmaybe-uninitialized] free(position); ^~~~~~~~~~~~~~ main.c:86:2: warning: 'pi' may be used uninitialized in this function [-Wmaybe-uninitialized] free(pi); ^~~~~~~~