< c‎ | io
File input/output

File access
Direct input/output
Unformatted input/output
(until C11)(since C11)
Formatted input
Formatted output
File positioning
Error handling
Operations on files
Defined in header <stdio.h>
int puts( const char *str );

Writes every character from the null-terminated string str and one additional newline character '\n' to the output stream stdout, as if by repeatedly executing fputc.

The terminating null character from str is not written.


[edit] Parameters

str - character string to be written

[edit] Return value

On success, returns a non-negative value

On failure, returns EOF and sets the error indicator (see ferror()) on stream.

[edit] Notes

The puts function appends the newline character to the output, while fputs function does not.

Different implementations return different non-negative numbers: some return the last character written, some return the number of characters written (or INT_MAX if the string was longer than that), some simply return a non-negative constant.

A typical cause of failure for puts is running out of space on the file system, when stdout is redirected to a file.

[edit] Example

#include <stdio.h>
int main(void)
    int rc = puts("Hello World");
    if (rc == EOF)
       perror("puts()"); // POSIX requires that errno is set


Hello World

[edit] References

  • C11 standard (ISO/IEC 9899:2011):
  • The puts function (p: 333)
  • C99 standard (ISO/IEC 9899:1999):
  • The puts function (p: 299)
  • C89/C90 standard (ISO/IEC 9899:1990):
  • The puts function

[edit] See also

writes a character string to a file stream
(function) [edit]
prints formatted output to stdout, a file stream or a buffer
(function) [edit]