MSVC build errors > C4996

C4996: function may be unsafe or deprecated

warning C4996: 'strcpy': This function or variable may be unsafe. Consider using strcpy_s instead.

MSVC marks some C runtime functions as unsafe or deprecated. C4996 is a warning, but it stops the build when SDL checks (/sdl) or Treat Warnings As Errors are on, as in new projects.

Causes and fixes

1. A string function can overflow its buffer. Prefer std::string, or the bounded functions such as strcpy_s and snprintf.
2. A POSIX name is used. Functions such as open or strdup have ISO C++ names with an underscore: _open, _strdup.
3. Portable code must keep the standard functions. Define _CRT_SECURE_NO_WARNINGS in the project's preprocessor definitions, for that project only, rather than disabling C4996 for everything: it also reports your own [[deprecated]] functions.

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Related errors: C2065. See all guides.