# Special Tag Commands

Portfolio provides three special tag commands that have universal meanings in all system calls: `TAG_END`, `TAG_NOP`, and `TAG_JUMP`. By setting the `ta_Tag` field to these commands, you can control how TagArg arrays are processed by the system.

### TAG_END

The `TAG_END` command tells the system that this structure marks the end of an array of TagArg structures. The system stops scanning the array and goes no further.

### TAG_NOP

The `TAG_NOP` command tells the system to ignore the particular TagArg structure. The system just skips ahead and continues processing with the next TagArg structure.

### TAG_JUMP

The `TAG_JUMP` command links arrays of TagArg structures together. The `ta_Arg` field for this command must point to another array of TagArg structures. When the system encounters such a TagArg structure, it stops scanning the current array, and resumes scanning at the address specified by `ta_Arg`.