c - Differences between scanf & scanf_s -


this question has answer here:

what's difference between scanf , scanf_s in c. i'm using visual studio 13 , keeps on giving me errors when try use scanf.

both read formatted data standard input stream. '_s' microsoft's 'secure' versions.

these versions of scanf, _scanf_l, wscanf, _wscanf_l have security enhancements, described in security features in crt:

many old crt functions have newer, more secure versions. if secure function exists, older, less secure version marked deprecated , new version has _s ("secure") suffix.

in context, "deprecated" means function's use not recommended; not indicate function scheduled removed crt.

the secure functions not prevent or correct security errors; rather, catch errors when occur. perform additional checks error conditions, , in case of error, invoke error handler (see parameter validation).

for example, strcpy function has no way of telling if string copying big destination buffer. however, secure counterpart, strcpy_s, takes size of buffer parameter, can determine if buffer overrun occur. if use strcpy_s copy eleven characters ten-character buffer, error on part; strcpy_s cannot correct mistake, can detect error , inform invoking invalid parameter handler.

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