Editing Operating system (section)

=====Interrupt-driven I/O=====
{{Expand section|date=April 2022}}
When a [[user (computing)|computer user]] types a key on the keyboard, typically the character appears immediately on the screen. Likewise, when a user moves a [[computer mouse|mouse]], the [[Cursor (user interface)|cursor]] immediately moves across the screen. Each keystroke and mouse movement generates an ''interrupt'' called ''Interrupt-driven I/O''. An interrupt-driven I/O occurs when a process causes an interrupt for every character<ref name="sco-ch5-p294"/> or word<ref>{{cite book
 |title        = Users Handbook - PDP-7
 |id           = F-75
 |year         = 1965
 |url          = http://bitsavers.org/pdf/dec/pdp7/F-75_PDP-7userHbk_Jun65.pdf
 |section      = Program Interrupt Controller (PIC)
 |section-url  = http://bitsavers.org/pdf/dec/pdp7/F-75_PDP-7userHbk_Jun65.pdf#page=62
 |pages        = [http://bitsavers.org/pdf/dec/pdp7/F-75_PDP-7userHbk_Jun65.pdf#page=63 48]
 |publisher    = [[Digital Equipment Corporation]]
 |access-date  = April 20, 2022
 |archive-date = 10 May 2022
 |archive-url  = https://web.archive.org/web/20220510164742/http://bitsavers.org/pdf/dec/pdp7/F-75_PDP-7userHbk_Jun65.pdf
 |url-status   = live
}}</ref> transmitted.