Compilare: user.c:8:1: warning: return type defaults to ‘int’ [enabled by default] main(){ ^ user.c: In function ‘main’: user.c:16:1: warning: implicit declaration of function ‘strlen’ [-Wimplicit-function-declaration] len = strlen(secv); ^ user.c:16:7: warning: incompatible implicit declaration of built-in function ‘strlen’ [enabled by default] len = strlen(secv); ^ user.c:15:7: warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result [-Wunused-result] fscanf(file1, "%s", secv); ^