Scroll Down to See All▾
abortabsacosasctimeasctime_rasinassertatanatan2atexitatofatoiatolbsearchbtowccalloccatclosecatgetscatopenceilclearerrclockcoscoshctimectime_rdifftimediverferfcexitexpfabsfclosefdopenfeofferrorfflushfgetcfgetposfgetsfgetwcfgetwsfopenfprintffputcfputwsfreadfreefreopenfrexpfscanffseekfsetposftellfwidefwprintffwritefwscanfgetcgetchargetenvgetwcgetwchargmtimegmtime_rhypotisalnumisalphaisasciiisblankiscntrlisdigitisgraphislowerisprintispunctisspaceisupperiswalnumiswalphaiswblankiswcntrliswctypeiswdigitiswgraphiswloweriswprintiswpunctiswspaceiswupperiswxdigitisxdigitj0j1jnlabsldexpldivlocaleconvlocaltimelocaltime_rloglog10longjmpmallocmblenmbrlenmbrtowcmbsinitmbsrtowcsmbstowcsmbtowcmemchrmemcmpmemcpymemmovememsetmktimemodfnextafternextafterlnexttowardnexttowardlnl_langinfoperrorpowprintfputcputcharputenvputsputwcputwcharqsortquantexpd32quantexpd64quantexpd128quantized32quantized64quantized128samequantumd32raiserandrand_rreallocregcompregerrorregexecregfreeremoverenamerewindscanfsetbufsetjmpsetlocalesetvbufsignalsinsinhsnprintfsprintfsqrtsrandsscanfstrcasecmpstrcatstrchrstrcmpstrcollstrcpystrcspnstrerrorstrfmonstrftimestrlenstrncasecmpstrncatstrncmpstrncpystrpbrkstrptimestrrchrstrspnstrstrstrtodstrtod32strtod64strtod128strtofstrtokstrtok_rstrtolstrtoldstrtoulstrxfrmswprintfswscanfsystemtantanhtimetime64tmpfiletmpnamtoasciitolowertouppertowctranstowlowertowupperungetcungetwcva_argva_copyva_endva_startvfprintfvfscanfvfwscanfvprintfvscanfvsprintfvsnprintfvsscanfvswprintfvswscanfvwprintfvwscanfwcrtombwcscatwcschrwcscmpwcscollwcscpywcscpywcsftimewcslenwcsncatwcsncmpwcsncpywcspbrkwcsptimewcsrchrwcsrtombswcsspnwcsstrwcstodwcstod32wcstod64wcstod128wcstofwcstokwcstolwcstoldwcstombswcstoulwcsxfrmwctobwctombwctranswctypewcwidthwmemchrwmemcmpwmemcpywmemmovewmemsetwprintfwscanfy0y1yn



Function Details : vfwprintf

intvfwprintf(FILE * stream,const wchar_t * format,va_list args) ;

Return Type : int

Integer type (typically 4 bytes, -2,147,483,648 to 2,147,483,647)
Read about return values of vfwprintf function .

1st Parameter Type : FILE *

Pointer to FILE structure for file operations

1st Parameter

Pointer to the output stream where the formatted wide-character output will be written.

2nd Parameter Type : const wchar_t *

A pointer to a read-only wide-character string, where each character is of type `wchar_t`. Used for representing text in wide-character encoding to support extended character sets, such as Unicode. The string is null-terminated, with the terminator being a `wchar_t` with value 0.

2nd Parameter

Pointer to a null-terminated wide-character string specifying the format of the output. It may include format specifiers like `%ls`, `%d`, etc.

3rd Parameter Type : va_list

A data type used to hold information about variable arguments passed to a variadic function. It is initialized with `va_start`, used with `va_arg`, and cleaned up with `va_end`.

3rd Parameter

The variable argument list containing the values to be formatted and written. It must be initialized with `va_start`.

Read more about parameters of vfwprintf in parameters section
The vfwprintffunction in C language Writes formatted wide character output to the specified stream using a va_list.
vfwprintf is similar to fwprintf, but instead of taking a variable number of arguments, it takes a va_list that has been initialized by va_start. This function is useful for implementing custom variadic functions that need to forward their arguments to fwprintf for wide character output.
The vfwprintffunction takes 3 parameters:
  • •
    FILE * `stream`: Pointer to the output stream where the formatted wide-character output will be written.
  • •
    const wchar_t * `format`: Pointer to a null-terminated wide-character string specifying the format of the output. It may include format specifiers like `%ls`, `%d`, etc.
  • •
    va_list `args`: The variable argument list containing the values to be formatted and written. It must be initialized with `va_start`.
Writes a formatted wide-character output to the specified `stream` based on the format string `format` and the values in the `va_list` object `args`. Returns the number of wide characters written, or a negative value if an error occurs.
The vfwprintf function return value :
  • Returns the number of wide characters written, or a negative value if an error occurred

Output

This example demonstrates using vfwprintf in a custom logging function that can write wide character strings to different streams.