_putchar_nolock, _putwchar_nolock

Writes a character to stdout without locking.


int _putchar_nolock(
   int c
wint_t _putwchar_nolock(
   wchar_t c


Character to be written.

Return value

See putchar, putwchar.


putchar_nolock and _putwchar_nolock are identical to the versions without the _nolock suffix except that they aren't protected from interference by other threads. They might be faster because 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.

Generic-text routine mappings

Tchar.h routine _UNICODE and _MBCS not defined _MBCS defined _UNICODE defined
_puttchar_nolock _putchar_nolock _putchar_nolock _putwchar_nolock


Routine Required header
_putchar_nolock <stdio.h>
_putwchar_nolock <stdio.h> or <wchar.h>

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.


All versions of the C run-time libraries.


// crt_putchar_nolock.c
/* This program uses putchar to write buffer
* to stdout. 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_nolock( *p );


This is the line of output

See also

Stream I/O
fputc, fputwc
fgetc, fgetwc