Debug for Linux?
 

Hi!
I'm studying 8086 in Microprocessor II
Usually we write simple programs using MS-Dos's debug "command"
Is there a parallel Linux utility ?
Also are there any assemblers like MASM TASM ?

I would also like to clear some doubts:

1. In DOS we use interrupts like int 20,int 21 etc.. which perform certain
tasks.
Are these interrupts applicable to Linux also?

2.In Assembly since we deal directly with CPU isn't it a
security risk? (I have come across some debug routines which clear CMOS ,
destroy the hard disk partitions... !)

3.Why there r so many books written for Assembly Programming which are
specific to Dos based Assemblers and debug?
Is Unix implementation for Assembly Programming difficult ?

Please enlighten.