BSDCan2015 - ZI

BSDCan 2015
The Technical BSD Conference

Dan Langille
Stephen Bourne
Day Talks #1 - 12 June - 2015-06-12
Room DMS 1160
Start time 09:00
Duration 01:15
ID 612
Event type Lecture
Track Plenary
Language used for presentation English


The opening session

There will be a few short announcements before and after the keynote.

Steve Bourne will talk about about sh/adb which he has never covered before in public. These include:

  • sh memory management and interfaces used to interleave heap and stack these were not C stack
  • sh has no string length or any other "arbitrary" length restrictions and what that meant for implementation
  • sbrk and porting grief people had (things you dont think of when you write the code)
  • my opinion of shellshock
  • tricks used and why (eg using top bit of byte as quoted string marker)
  • reasons we did all this and wouldn't do it today
  • adb interesting problem it runs on one machine is debugging another and compiled on a third
  • why i wrote it (Algol68 port) and Dennis added overlays (exec)
  • invention of environment variables and why
  • How I talked Dennis into putting 'void' into C and other C changes
  • why setjmp and longjmp are a good idea (so I could write sh)
  • why Bill Joy wrote the C shell