"HANDLE" ON MS-DOS 21h FUNCTIONS

[Programmer_BR]

Please! I´m writing my on int 21h functions almos like MS-DOS, but I´m not understanding what and why is used "HANDLE" on some functions of MS-DOS Example:
Close File with Handle

mov bx, Handle <- what kind value it´s this! what is this ? ? ?
mov ah, 3Eh
int 21h

jc error_handler

Please if anyone knows this! help me !

[Programmer_BR]

hi everybody, I did this question but, I discover what and why it´s used a handle on many file IO MS-DOS int 21h. many thank´s to everybody!

[ASHLEY4]

"The handle is the offset into a process's JHT (Job Handle Table).
The JHT is the file handle structure located in the PSP of every Dos program and is by default limited to 20 entries."

The above quote is from this book "Dissecting DOS" by M Podanoffsky.
And is a good book for writing a Dos clone OS.

ASHLEY4.

[Programmer_BR]

tanks!