_fputc_nolock, _fputwc_nolock

Writes a character to a stream without locking the thread.

int _fputc_nolock(
   int c,
   FILE *stream 
wint_t _fputwc_nolock(
   wchar_t c,
   FILE *stream 


  • c
    Character to be written.

  • stream
    Pointer to the FILE structure.

Return Value

Each of these functions returns the character written. For error information, see fputc, fputwc.


_fputc_nolock and _fputwc_nolock are identical to fputc and fputwc, respectively, except that they are not protected from interference by other threads. They might be faster because they do not 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.

The two functions behave identically if the stream is opened in ANSI mode. _fputc_nolock does not currently support output into a UNICODE stream.

Generic-Text Routine Mappings

Tchar.h routine

_UNICODE and _MBCS not defined

_MBCS defined

_UNICODE defined







Required header




<stdio.h> or <wchar.h>

The console is not supported in Windows Store 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 Windows Store apps. For more compatibility information, see Compatibility.


// crt_fputc_nolock.c
// This program uses _fputc_nolock
// to send a character array to stdout.

#include <stdio.h>

int main( void )
   char strptr1[] = "This is a test of _fputc_nolock!!\n";
   char *p;

   // Print line to stream using fputc. 
   p = strptr1;
   while( (*p != '\0') && _fputc_nolock( *(p++), stdout ) != EOF ) ;

This is a test of _fputc_nolock!!

.NET Framework Equivalent

See Also


Stream I/O

fgetc, fgetwc

putc, putwc