C++ mktime returning random dates

Question

I\'m trying to convert a date string to a time_t, but mktime() is returning seemingly random dates:

string datetime = \"2014-12-10 10:30\";
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Answer 1

You need to properly zero-initialize all of the other fields of the struct tm instance before calling strptime(), since it doesn't necessarily initialize every field. From the strptime() POSIX specification:

It is unspecified whether multiple calls to strptime() using the same tm structure will update the current contents of the structure or overwrite all contents of the structure. Conforming applications should make a single call to strptime() with a format and all data needed to completely specify the date and time being converted.

For example, this should suffice:

struct tm tmInfo = {0};