The GNU C Library - Simple Output

Simple Output by Characters or Lines

This section describes functions for performing character- and line-oriented output.

These functions are declared in the header file `stdio.h'.

Function int fputc (int c, FILE *stream)

The fputc function converts the character c to type unsigned char , and writes it to the stream stream. EOF is returned if a write error occurs; otherwise the character c is returned.

Function int putc (int c, FILE *stream)

This is just like fputc , except that most systems implement it as a macro, making it faster. One consequence is that it may evaluate the stream argument more than once. putc is usually the best function to use for writing a single character.

Function int putchar (int c)

The putchar function is equivalent to putc with stdout as the value of the stream argument.

Function int fputs (const char *s, FILE *stream)

The function fputs writes the string s to the stream stream. The terminating null character is not written. This function does not add a newline character, either. It outputs only the chars in the string.

This function returns EOF if a write error occurs, and otherwise a non-negative value.

For example:

	fputs ("Are ", stdout);
	fputs ("you ", stdout);
	fputs ("hungry?\n", stdout);

outputs the text `Are you hungry?' followed by a newline.

Function int puts (const char *s)

The puts function writes the string s to the stream stdout followed by a newline. The terminating null character of the string is not written.

puts is the most convenient function for printing simple messages. For example:

	puts ("This is a message.");

Function int putw (int w, FILE *stream)

This function writes the word w (that is, an int ) to stream. It is provided for compatibility with SVID, but we recommend you use fwrite instead (see Block Input/Output).