cppreference.com > Standard C I/O > sprintf sprintf Syntax:
      #include <stdio.h>
      int sprintf( char *buffer, const char *format, ... );
The sprintf() function is just like printf(), except that the output is sent to buffer. The return value is the number of characters written. For example:
       char string[50];
       int file_number = 0;

       sprintf( string, "file.%d", file_number );
       file_number++;
       output_file = fopen( string, "w" );
Note that sprintf() does the opposite of a function like (Standard C String and Character) atoi() -- where (Standard C String and Character) atoi() converts a string into a number, sprintf() can be used to convert a number into a string. For example, the following code uses sprintf() to convert an integer into a string of characters:
       char result[100];
       int num=24;
       sprintf( result, "%d", num );
Related topics: (Standard C String and Character) atof (Standard C String and Character) atoi (Standard C String and Character) atol fprintf printf