Deprecated CRT Functions

Deprecated CRT functions and their recommended replacements.

Deprecated POSIX functions

The following POSIX names for functions are deprecated. In most cases, prepending an underscore character gives the standard equivalent name. Note that some functions have more secure versions ("_s" suffix).

You can also eliminate POSIX deprecation warnings by defining _CRT_NONSTDC_NO_DEPRECATE.

Deprecated function	Replacement function
access	_access, _access_s
cabs	_cabs
cgets	_cgets, _cgets_s
chdir	_chdir
chmod	_chmod
chsize	_chsize, _chsize_s
close	_close
cprintf	_cprintf, _cprintf_s
cputs	_cputs
creat	_creat
cscanf	_cscanf, _cscanf_s
cwait	_cwait
dup	_dup
dup2	_dup2
ecvt	_ecvt, _ecvt_s
eof	_eof
execl	_execl
execle	_execle
execlp	_execlp
execlpe	_execlpe
execv	_execv
execve	_execve
execvp	_execvp
execvpe	_execvpe
fcloseall	_fcloseall
fcvt	_fcvt, _fcvt_s
fdopen	_fdopen
fgetchar	_fgetchar
filelength	_filelength
fileno	_fileno
flushall	_flushall
fputchar	_fputchar, _fputwchar
gcvt	_gcvt, _gcvt_s
getch	_getch
getche	_getche
getcwd	_getcwd, _wgetcwd
getpid	_getpid
getw	_getw
hypot	_hypot
inp	_inp
inpw	_inpw
isascii	__isascii
isatty	_isatty
iscsym	__iscsym
iscsymf	__iscsymf
itoa	_itoa, _itoa_s
j0	_j0
j1	_j1
jn	_jn
kbhit	_kbhit
lfind	_lfind, _lfind_s
locking	_locking
lsearch	_lsearch, _lsearch_s
lseek	_lseek
ltoa	_ltoa, _ltoa_s
memccpy	_memccpy
memicmp	_memicmp
mkdir	_mkdir
mktemp	_mktemp, _mktemp_s
open	_open
outp	_outp
outpw	_outpw
putch	_putch
putenv	_putenv, _putenv_s
putw	_putw
read	_read
rmdir	_rmdir
rmtmp	_rmtmp
setmode	_setmode
sopen	_sopen, _sopen_s
spawnl	_spawnl
spawnle	_spawnle
spawnlp	_spawnlp
spawnlpe	_spawnlpe
spawnv	_spawnv
spawnve	_spawnve
spawnvp	_spawnvp
spawnvpe	_spawnvpe
strcmpi	_stricmp
strdup	_strdup
stricmp	_stricmp
strlwr	_strlwr, _strlwr_s
strnicmp	_strnicmp
strnset	_strnset, _strnset_s
strrev	_strrev
strset	_strset, _strset_s
strupr	_strupr, _strupr_s
swab	_swab
tell	_tell
tempnam	_tempnam
toascii	__toascii
tzset	_tzset
ultoa	_ultoa, _ultoa_s
umask	_umask, _umask_s
ungetch	_ungetch
unlink	_unlink
wcsdup	_wcsdup
wcsicmp	_wcsicmp
wcsicoll	_wcsicoll
wcslwr	_wcslwr, _wcslwr_s
wcsnicmp	_wcsnicmp
wcsnset	_wcsnset, _wcsnset_s
wcsrev	_wcsrev
wcsset	_wcsset, _wcsset_s
wcsupr	_wcsupr, _wcsupr_s
write	_write
y0	_y0
y1	_y1
yn	_yn

Security-enhanced functions

The following functions should be avoided because a more secure version of the function should be used instead. For more information, see Security Enhancements in the CRT.

Deprecated function	Security-enhanced replacement
_alloca	_malloca
asctime	asctime_s
_cgets, _cgetws	_cgets_s, _cgetws_s
_chsize	_chsize_s
_controlfp	_controlfp_s
_creat	_sopen_s
_cscanf	_cscanf_s
_cscanf_l	_cscanf_s_l
ctime	ctime_s
_ctime32	_ctime32_s
_ctime64	_ctime64_s
_cwscanf	_cwscanf_s
_cwscanf_l	_cwscanf_s_l
_ecvt	_ecvt_s
_fcvt	_fcvt_s
fopen	fopen_s
freopen	freopen_s
fscanf	fscanf_s
_fscanf_l	_fscanf_s_l
fwscanf	fwscanf_s
_fwscanf_l	_fwscanf_s_l
_gcvt	_gcvt_s
getenv	getenv_s
gets, _getws	gets_s, _getws_s
gmtime	_gmtime_s
_gmtime32	_gmtime32_s
_gmtime64	_gmtime64_s
_i64toa	_i64toa_s
_i64tow	_i64tow_s
_itoa	_itoa_s
_itow	_itow_s
localtime	_localtime_s
_localtime32	_localtime32_s
_localtime64	_localtime64_s
_ltoa, _ltow	_ltoa_s, _ltow_s
_mbccpy	_mbccpy_s
_mbccpy_l	_mbccpy_s_l
_mbscat	_mbscat_s
_mbscpy	_mbscpy_s
_mbslwr, _mbslwr_l	_mbslwr_s, _mbslwr_s_l
_mbsnbcat, _mbsnbcat_l	_mbsnbcat_s, _mbsnbcat_s_l
_mbsnbcpy, _mbsnbcpy_l	_mbsnbcpy_s, _mbsnbcpy_s_l
_mbsnbset	_mbsnbset_s
_mbsnbset_l	_mbsnbset_s_l
_mbsncat	_mbsncat_s
_mbsncat_l	_mbsncat_s_l
_mbsncpy	_mbsncpy_s
_mbsncpy_l	_mbsncpy_s_l
_mbsnset	_mbsnset_s
_mbsnset_l	_mbsnset_s_l
mbsrtowcs	mbsrtowcs_s
_mbsset	_mbsset_s
_mbsset_l	_mbsset_s_l
_mbstok	_mbstok_s
_mbstok_l	_mbstok_s_l
mbstowcs, _mbstowcs_l	mbstowcs_s, _mbstowcs_s_l
_mbsupr, _mbsupr_l	_mbsupr_s, _mbsupr_s_l
memcpy	memcpy_s
memmove	memmove_s
_mktemp	_mktemp_s
_open	_sopen_s
scanf	scanf_s
_scanf_l	_scanf_s_l
_searchenv	_searchenv_s
setbuf	setvbuf
_snprintf	_snprintf_s
_snprintf_l	_snprintf_s_l
_snscanf	_snscanf_s
_snscanf_l	_snscanf_s_l
_snwprintf	_snwprintf_s
_snwprintf_l	_snwprintf_s_l
_snwscanf	_snwscanf_s
_snwscanf_l	_snwscanf_s_l
_sopen	_sopen_s
_splitpath	_splitpath_s
sprintf	sprintf_s
_sprintf_l	_sprintf_s_l
sscanf	sscanf_s
_sscanf_l	_sscanf_s_l
strcat	strcat_s
strcpy	strcpy_s
_strdate	_strdate_s
strerror, _strerror	strerror_s, _strerror_s
_strlwr, _strlwr_l	_strlwr_s, _strlwr_s_l
strncat, _strncat_l	strncat_s, _strncat_s_l
strncpy, _strncpy_l	strncpy_s, _strncpy_s_l
_strnset	_strnset_s
_strnset_l	_strnset_s_l
_strset	_strset_s
_strset_l	_strset_s_l
_strtime	_strtime_s
strtok	strtok_s
_strtok_l	_strtok_s_l
_strupr, _strupr_l	_strupr_s, _strupr_s_l
swprintf	swprintf_s
_swprintf_l	_swprintf_s_l
swscanf	swscanf_s
_swscanf_l	_swscanf_s_l
tmpfile	tmpfile_s
_ui64toa, _ui64tow	_ui64toa_s, _ui64tow_s
_ultoa, _ultow	_ultoa_s, _ultow_s
_umask	_umask_s
vsnprintf, _vsnprintf, _vsnprintf_l, _vsnwprintf, _vsnwprintf_l	vsnprintf_s, _vsnprintf_s, _vsnprintf_s_l, _vsnwprintf_s, _vsnwprintf_s_l
vsprintf, _vsprintf_l, vswprintf, _vswprintf_l, __vswprintf_l	vsprintf_s, _vsprintf_s_l, vswprintf_s, _vswprintf_s_l
_wasctime	_wasctime_s
_wcreat	_wsopen_s
wcrtomb	wcrtomb_s
wcscat	wcscat_s
wcscpy	wcscpy_s
_wcserror, __wcserror	_wcserror_s, __wcserror_s
_wcslwr, _wcslwr_l	_wcslwr_s, _wcslwr_s_l
wcsncat, wcsncat_l	wcsncat_s, _wcsncat_s_l
_wcsncpy, _wcsncpy_l	wcsncpy_s, _wcsncpy_s_l
_wcsnset, _wcsnset_l	_wcsnset_s, _wcsnset_s_l
wcsrtombs	wcsrtombs_s
_wcsset, _wcsset_l	_wcsset_s_wcsset_s_l
wcstok, _wcstok_l	wcstok_s, _wcstok_s_l
wcstombs, _wcstombs_l	wcstombs_s, _wcstombs_s_l
_wcsupr_l, _wcsupr	_wcsupr_s, _wcsupr_s_l
_wctime, _wctime32, _wctime64	_wctime_s, _wctime32_s, _wctime64_s
wctomb, _wctomb_l	wctomb_s, _wctomb_s_l
_wfopen	_wfopen_s
_wfreopen	_wfreopen_s
_wgetenv	_wgetenv_s
wmemcpy	wmemcpy_s
wmemmove	wmemmove_s
_wmktemp	_wmktemp_s
_wopen	_wsopen_s
_wscanf, _wscanf_l	_wscanf_s, _wscanf_s_l
_wsearchenv	_wsearchenv_s
_wsopen	_wsopen_s
_wsplitpath	_wsplitpath_s
_wstrdate	_wstrdate_s
_wstrtime	_wstrtime_s

Functions with Secure Template Overloads

Some of the functions in the preceding section have secure template overloads which can eliminate deprecation warnings by replacing calls to deprecated functions with calls to the new secure versions of those functions. For more information, see Secure Template Overloads.

Deprecated functions with secure template overloads
_cgets, _cgetws
gets, _getws
_itoa, _i64toa, _ui64toa, _itow, _i64tow, _ui64tow
_ltoa, _ltow
_mbsnbcat, _mbsnbcat_l
_mbsnbcpy, _mbsnbcpy_l
mbsrtowcs
mbstowcs, _mbstowcs_l
_mktemp, _wmktemp
_searchenv, _wsearchenv
_snprintf, _snprintf_l, _snwprintf, _snwprintf_l
sprintf, _sprintf_l, swprintf, _swprintf_l, __swprintf_l
strcat, wcscat, _mbscat
strcpy, wcscpy, _mbscpy
_strdate, _wstrdate
_strlwr, _wcslwr, _mbslwr, _strlwr_l, _wcslwr_l, _mbslwr_l
strncat, _strncat_l, wcsncat, wcsncat_l, _mbsncat _mbsncat_l
strncpy, _strncpy_l, wcsncpy, _wcsncpy_l, _mbsncpy, _mbsncpy_l
_strtime, _wstrtime
_strupr, _strupr_l, _mbsupr, _mbsupr_l, _wcsupr_l, _wcsupr
_ultoa, _ultow
vsnprintf, _vsnprintf, _vsnprintf_l, _vsnwprintf, _vsnwprintf_l
vsprintf, _vsprintf_l, vswprintf, _vswprintf_l, __vswprintf_l
wcrtomb
wcsrtombs
wcstombs, _wcstombs_l

See Also

Concepts

Run-Time Routines by Category