-void idea_ofb64_encrypt(in, out, length, schedule, ivec, num)
-unsigned char *in;
-unsigned char *out;
-long length;
-IDEA_KEY_SCHEDULE *schedule;
-unsigned char *ivec;
-int *num;
+void idea_ofb64_encrypt(const unsigned char *in, unsigned char *out,
+ long length, IDEA_KEY_SCHEDULE *schedule,
+ unsigned char *ivec, int *num)