Difference between puts() and printf() for printing a string in C

The C header file defines the puts() and printf() functions, which print a string on the console. In this article, we will discuss difference between puts() and printf() method in C. But before discussing their differences, we must know about the puts() and printf() method.

What is the puts() Function?

When writing a string to the console, the puts() function automatically appends the new line character "\n".

Syntax:

It has the following syntax:

Parameters

str: It accepts as input a string that is null-terminated.

Return Value

• End-of-File is returned in the event of an error; a non-negative value is returned in the event of a successful output.

What is the printf() Function?

In addition to printing data to the console, the printf() method can print formatted data based on a given format string.

Syntax:

It has the following syntax:

Parameters

• format_string:Either a plain string or a string with format specifiers can be used.
• Arguments: The values that must be shown are those of the variable names.

Return Value

• If not, it provides the number of characters that were successfully entered into the console.

Efficiency:

• Puts() does not require formatting. Hence, it is typically faster and more effective when printing strings.
• Because of its formatting capabilities, the printf() has a higher processing overhead than puts(), which could lead to a marginally slower output of simple strings.

Formatting:

• Puts() prints the string followed by a newline character; it provides no formatting
• Printf() lets us use format specifiers to set various formatting parameters, including alignment, field width, precision, and more.

Usage:

• Puts() adds a newline character \n at the end of the string by default and is only intended to print strings. The string to be printed is the only argument required.
• A more flexible function, the printf(), may print strings and other data types and manage different formatting styles. With the use of format specifiers, it permits more intricate output formatting. The Printf() can print a string with the %s format specifier.

Which of the following two should be preferred?

For printing a string, puts() may be preferable over printf() since it is typically less expensive (puts() implementation is typically simpler than printf()), and printf() may produce unexpected results if the string contains formatting characters like '%s'. Moreover, using printf() on a user-input string str could lead to security problems.

Keep in mind that puts() advances the cursor to the following line.

Use the following puts() variation if we do not want the cursor to advance to the next line.

fputs(str, stdout)

Main differences between the printf() and puts()

There are several differences between the printf() and puts() in C. Some main differences of these functions are as follows:

Example 1:

Output:

Example 2

The below C program demonstrated the use of fputs.

Output:

Example 3

The below C program demonstrates the unexpected behavior when %s is used in the printf() function.

Output: