I interviewed Brian J. Fox, the creator of Bash

Re:I interviewed Brian J. Fox, the creator of Bash by saurik on Thursday September 02, 2021 @01:05PM (#28394560)

https://www.pcmag.com/news/linux-is-now-on-mars-thanks-to-na...

> Linux Is Now on Mars, Thanks to NASA's Perseverance Rover

> Previous NASA Mars rovers mostly used an operating system from Wind River Systems. But this time, the space agency chose Linux for Perseverance's Ingenuity helicopter drone.

https://linuxunplugged.com/396

> [audio] Tim Canham, the Mars Helicopter Operations Lead, shares Linux’s origins at JPL and how it ended up running on multiple boxes on Mars.

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Re:I interviewed Brian J. Fox, the creator of Bash by mst on Friday September 03, 2021 @01:33AM (#28400729)

I know one of the DoD sysadmins who was involved in making this happen, and have taken great joy in listening to her brag about it any time she likes. Never gets old for me :D

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Re:I interviewed Brian J. Fox, the creator of Bash by capableweb on Thursday September 02, 2021 @01:08PM (#28394588)

"I stopped at", saying software on a flying helicopter on Mars "isn't mission critical" and that bash would never pass any verification process at NASA does indeed sound like you're dissing bash here. If your intent was to leave some sort of feedback or opinion that can improve things and look less like a "diss", then you probably wanna give it another go.

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Re:I interviewed Brian J. Fox, the creator of Bash by SavantIdiot on Friday September 03, 2021 @02:09PM (#28407406)

Better?

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Re:I interviewed Brian J. Fox, the creator of Bash by dooglius on Thursday September 02, 2021 @01:07PM (#28394580)

From what I've read, one of the things the helicopter project did was to see how well ignoring the usual heavy verification would go--it used consumer-grade off-the-shelf hardware as well, for instance.

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Re:I interviewed Brian J. Fox, the creator of Bash by capableweb on Thursday September 02, 2021 @01:09PM (#28394608)

> From what I've read

Could you recall any sources to this?

Just because they are using OTS hardware doesn't mean it doesn't go through verification and testing, it just means they are buying hardware instead of making it themselves.

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Re:I interviewed Brian J. Fox, the creator of Bash by samizdis on Thursday September 02, 2021 @02:59PM (#28395949)

There's this recent-ish news article:

How the First Helicopter on Mars Uses Off-the-Shelf Hardware and Linux

https://thenewstack.io/how-the-first-helicopter-on-mars-uses...

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Re:I interviewed Brian J. Fox, the creator of Bash by _joel on Thursday September 02, 2021 @01:17PM (#28394722)

They have 2 sets of RAM and a RAD hardened FPGA that checks for bitfips in the memory. It can restart one that quickly that it can do it mid-flight. It's amazing what possibilities this could open up as doing intensive image processing on RAD hardened is expensive, or not even possible as it lags behind the state of the art.

edit: found the paper https://trs.jpl.nasa.gov/bitstream/handle/2014/46229/CL%2317...

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Re:I interviewed Brian J. Fox, the creator of Bash by nexuist on Thursday September 02, 2021 @01:27PM (#28394852)

Why would you be surprised? Out of nearly a decade of using Bash on Linux I don't think I have ever run into a bash bug or issue. There's been bugs with utilities like sudo of course, but those aren't Bash.

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Re:I interviewed Brian J. Fox, the creator of Bash by bmoyles on Thursday September 02, 2021 @06:04PM (#28397957)

It happens... I can think of a couple that bit me in the last 5 years or so. Some of them felt like bugs but were flagged as new features in later releases like this one from 4.4... spent way too long trying to figure out why this worked under 4.4 but not 4.3 and didn't even consider a bug, let alone a feature at the time. I was convinced it was something I did wrong :P

"a. Using ${a[@]} or ${a[*]} with an array without any assigned elements when the nounset option is enabled no longer throws an unbound variable error."

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Re:I interviewed Brian J. Fox, the creator of Bash by chasil on Thursday September 02, 2021 @02:31PM (#28395617)

From the anguish of those who try to implement the POSIX shell, I understand that edge cases are far from difficult to find. The Almquist shell (Debian Dash) is cited for not using lex/yacc to implement the parser, and described as untrustworthy.

https://archive.fosdem.org/2018/schedule/event/code_parsing_...

A major goal of this later ADA implementation is readability, in addition to (Windows) performance and ADA's safety.

https://archive.fosdem.org/2019/schedule/event/ada_shell/

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Re:I interviewed Brian J. Fox, the creator of Bash by qiqitori on Friday September 03, 2021 @12:25AM (#28400394)

Not sure if this counts as "running into an issue", but this bash issue is pretty famous: https://en.wikipedia.org/wiki/Shellshock_(software_bug)

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Re:I interviewed Brian J. Fox, the creator of Bash by pabs3 on Friday September 03, 2021 @12:15AM (#28400350)

There are design flaws and edge cases in bash though, lots of them come up when trying to automatically show the exit code of the last command and when trying to automatically show whether or not the output of the last command ended in a line ending character.

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Re:I interviewed Brian J. Fox, the creator of Bash by SavantIdiot on Thursday September 02, 2021 @02:43PM (#28395766)

"I don't think I have ever run into a bash bug or issue."

That is not a statement about a formally verifiable program that I would base a billion-dollar program on.

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Re:I interviewed Brian J. Fox, the creator of Bash by count on Thursday September 02, 2021 @05:42PM (#28397739)

Formally verified programs often still have bugs. AWS S2N, for example, currently has hundreds of open issues and identified bugs, despite being the subject of a continuous formal verification program.

Bash powers probably hundreds of billions of dollars worth of critical infrastructure...

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Re:I interviewed Brian J. Fox, the creator of Bash by pabs3 on Friday September 03, 2021 @12:17AM (#28400366)

There are attempts at formal analysis of shell scripts, for eg:

https://colis.irif.fr/ https://github.com/colis-anr/morbig

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Re:I interviewed Brian J. Fox, the creator of Bash by nexuist on Friday September 03, 2021 @12:35PM (#28406391)

My point being that whatever other software runs on this thing is far more likely to contain hidden bugs than bash has given its age and widespread distribution. It seems weird to single out bash as opposed to the hundreds of other random packages on any given distro.

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Re:I interviewed Brian J. Fox, the creator of Bash by varjag on Thursday September 02, 2021 @03:26PM (#28396254)

Ariane 5 bug was formally verified.

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Re:I interviewed Brian J. Fox, the creator of Bash by sigzero on Thursday September 02, 2021 @04:45PM (#28397129)

No it really wasn't.

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Re:I interviewed Brian J. Fox, the creator of Bash by tyingq on Thursday September 02, 2021 @01:35PM (#28394954)

Assuming a posix-ish shell were a requirement for some NASA mission, what shell do you think might pass their verification process?

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Re:I interviewed Brian J. Fox, the creator of Bash by bitbang on Thursday September 02, 2021 @05:22PM (#28397530)

/bin/true

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