Описание тега strcat-s
NoneStrcat_s is a proposed safer version of strcat
In C programming, strcat_s is a safe version of the strcat function. Along with strcpy_s this functions (defined in the ISO/IEC TR 24731 [ PDF]) add an additional argument that specifies the maximum size of the destination and a return value that indicates whether the operation was successful
This function is supported in Microsoft's C library among others but there are criticism to the ISO proposal in general and, for example, glibc has not adopted them.