linux fprintf格式化输出技巧有哪些

fprintf ?????????????????? C ????

1. ????????????:

   #include
   
   int main() {
       int a = 42;
       float b = 3.14;
       const char *s = "Hello, World!";
   
       FILE *file = fopen("output.txt", "w");
       if (file == NULL) {
           printf("Error opening file.\n");
           return 1;
       }
   
       fprintf(file, "Integer: %d\n", a);
       fprintf(file, "Float: %.2f\n", b);
       fprintf(file, "String: %s\n", s);
   
       fclose(file);
       return 0;
   }
   

2. ???????????:

   fprintf(file, "Hexadecimal: %x\n", a);
   fprintf(file, "Octal: %o\n", a);
   

3. ??????:

   void *ptr = &a;
   fprintf(file, "Pointer address: %p\n", ptr);
   

4. ??????????:

   fprintf(file, "With leading zeros: d\n", a);
   

5. ??????????????:

   fprintf(file, "Left-aligned: %-10s\n", s);
   fprintf(file, "Right-aligned: s\n", s);
   

6. ?????????????:

   fprintf(file, "Scientific notation: %e\n", b);
   

7. ????????(va_list)????????????:

   #include 
   
   void custom_fprintf(FILE *file, const char *format, ...) {
       va_list args;
       va_start(args, format);
       vfprintf(file, format, args);
       va_end(args);
   }
   
   int main() {
       // ... (open the file and declare variables)
       custom_fprintf(file, "Integer: %d\n", a);
       custom_fprintf(file, "Float: %.2f\n", b);
       custom_fprintf(file, "String: %s\n", s);
       // ... (close the file)
   }
   

??????????????? fprintf ??????,??????,?????????????(???????????)???????