I have never used octal numbers in my code nor come across any code that used it. I bet you have. According to the standard, numeric literals which start with zero are octal. This includes, trivially, 0. Every time you have used or seen a literal zero, this has been octal. Strange but true.
If you are making child support payments in Texas, the law generally requires you to do so until your child turns 18, which is the age that marks adulthood in the state, or when he graduates from high school -- whichever comes later.
When a child turns 19 years old, the child is emancipated by operation of law, and the non-custodial parent's obligation to pay current child support terminates. An exception is if the child is incapacitated. In this case, the child support continues during the incapacity or until further order of the court.