Function 3Ch (60)        Create a File (CREAT)

    Create a new file or open and truncate an existing file to zero
    length.

       On entry:      AH         3Ch
                      CX         File attribute
                      DS:DX      Pointer to filename (ASCIIZ string)

       Returns:       AX         File handle, if CF is not set, or
                                 Error code, if CF is set

       Error codes:   3          Path not found
                      4          No handle available
                      5          Access denied (file is read-only, or root
                                 directory is full)

                      Call Function 59h for extended error code information
                      (DOS 3.0 and above).

       Network:       Requires Create access rights.

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    This function opens the file whose pathname is specified in the ASCIIZ
    string at DS:DX. If the file doesn't already exist, it is created.
    Warning: If a file with the specified name already exists, it is
    truncated to zero length, effectively deleting the old data from the
    file. The file is opened for read/write.

       Notes:         The CX register specifies the attribute of the file
                      you're creating, as follows:

                            CX       Attribute specified
                            00h      Normal
                            01h      Read-only
                            02h      Hidden
                            04h      System

                      Sum the values to combine attributes.

                      Information can be written to a file created in
                      Read-only mode. However, using this function to open
                      an existing read-only file will generate an error.

                      The CHMOD function (43h) can be used to change the
                      file's attribute.