Re: [TUHS] sh and goto

Message: 4 Date: Mon, 30 Nov 2020 19:59:18 -0800 (PST) From: jason-tuhs(a)shalott.net To: tuhs(a)minnie.tuhs.org Subject: Re: [TUHS] The UNIX Command Language (1976) Message-ID: <alpine.LRH.2.23.453.2011301946410.14253(a)waffle.shalott.net> <alpine.LRH.2.23.453.2011301946410.14253(a)waffle.shalott.net> Content-Type: text/plain; charset="utf-8"; Format="flowed" "The UNIX Command Language is the first-ever paper published on the Unix shell. It was written by Ken Thompson in 1976." https://github.com/susam/tucl Thanks for that. This reminded me that the Thompson shell used goto for flow control, which I had forgotten. Bourne commented on the omission of goto from the Bourne shell, "I eliminated goto in favour of flow control primitives like if and for. This was also considered rather radical departure from the existing practice." Was this decision contentious at all? Was there a specific reason for goto's exclusion in the Bourne shell? Thanks. -Jason At the time it may have raised a few eyebrows but I don't recall much discussion about it then. My email tracks at the time don't mention it. Doug McIlroy or Steve Johnson (or Ken) on this forum might recall differently. At the time scripts were not that complicated and so error recovery to a far off place in the script was not common. As an aside I did persuade Dennis to add "setjmp" and "longjmp" so the shell code itself could recover from some kinds of script errors. So I did not have a "religious" aversion to "goto" at the time. Steve