C++ Programming/Code/Standard C Library/Functions/sprintf

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sprintf[edit]

Syntax
#include <cstdio>
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 atoi() -- where 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 );

This code is similar, except that it converts a floating-point number into an array of characters:

char result[100];
float fnum = 3.14159;
sprintf( result, "%f", fnum );
Related topics
fprintf - printf
(Standard C String and Character) atof - atoi - atol