bson_iter_find man page
bson_iter_find — bson_iter_find()
bool bson_iter_find (bson_iter_t *iter, const char *key);
iter: A bson_iter_t.
key: A string containing the requested key.
The bson_iter_find() function shall advance iter to the element named key or exhaust all elements of iter. If iter is exhausted, false is returned and iter should be considered invalid.
key is case-sensitive. For a case-folded version, see bson_iter_find_case().
true is returned if the requested key was found. If not, iter was exhausted and should now be considered invalid.
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