Chapter 3 of the "Programmers Manual for Vx Solutions" ("23230_Verix_V_Operating_System_Programmers_Manual.pdf") is all about file management and contains all the functions I typically use when dealing with data files on the terminal. Go read through that and I think you'll find everything you need.

To get you started, you'll want to use open together with the flags you want

• O_RDONLY (read only)
• O_WRONLY (write only)
• O_RDWR (read and write)
• O_APPEND (Opens with the file position pointer at the end of the file)
• O_CREAT (create the file if it doesn't already exist),
• O_TRUNC (truncate/delete previous contents if the file already exists),
• O_EXCL (Returns error value if the file already exists)

On success, open will return a positive integer that is a handle which can be used for subsequent access to the file. On failure, it returns -1;

When the file is open, you can use read and write to manipulate the contents.