putchar, putwchar

Writes a character to stdout.

Syntax

int putchar(
   int c
);
wint_t putwchar(
   wchar_t c
);

Parameters

c
Character to be written.

Return value

Returns the character written. To indicate an error or end-of-file condition, putc and putchar return EOF; putwc and putwchar return WEOF. For all four routines, use ferror or feof to check for an error or end of file. If passed a null pointer for stream, these functions generate an invalid parameter exception, as described in Parameter validation. If execution is allowed to continue, they return EOF or WEOF, and set errno to EINVAL.

For more information about return codes, see errno, _doserrno, _sys_errlist, and _sys_nerr.

Remarks

The putc routine writes the single character c to the output stream at the current position. Any integer can be passed to putc, but only the lower 8 bits are written. The putchar routine is identical to putc( c, stdout ). For each routine, if a read error occurs, the error indicator for the stream is set. putc and putchar are similar to fputc and _fputchar, respectively, but are implemented both as functions and as macros (see Recommendations for choosing between functions and macros). putwc and putwchar are wide-character versions of putc and putchar, respectively.

The versions with the _nolock suffix are identical except that they aren't protected from interference by other threads. They may be faster since they don't incur the overhead of locking out other threads. Use these functions only in thread-safe contexts such as single-threaded applications or where the calling scope already handles thread isolation.

By default, this function's global state is scoped to the application. To change this behavior, see Global state in the CRT.

Generic-text routine mappings

Requirements

The console isn't supported in Universal Windows Platform (UWP) apps. The standard stream handles that are associated with the console, stdin, stdout, and stderr, must be redirected before C run-time functions can use them in UWP apps. For more compatibility information, see Compatibility.

Libraries

All versions of the C run-time libraries.

Example

// crt_putchar.c
/* This program uses putc to write buffer
* to a stream. If an error occurs, the program
* stops before writing the entire buffer.
*/

#include <stdio.h>

int main( void )
{
   FILE *stream;
   char *p, buffer[] = "This is the line of output\n";
   int  ch;

   ch = 0;

   for( p = buffer; (ch != EOF) && (*p != '\0'); p++ )
      ch = putchar( *p );
}

Output

This is the line of output

See also

Stream I/O
fputc, fputwc
getc, getwc