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As the author of a POSIX standard utility, I would advise you to only reach for such utilities when portability is the most important thing. POSIX utilities ar

As the author of a POSIX standard utility, I would advise you to only reach for such utilities when portability is the most important thing. POSIX utilities are not great. Lex and Yacc included.

chasil 2y ago
Is your criticism of the relationship of the lexer and the parser, or something more fundamental? Is an LR parser expressed in BNF notation unsatisfactory? I say this only as it has been many years since I have written one, but I thought this OCaml presentation on a POSIX shell held the structure in high regard. https://archive.fosdem.org/2018/schedule/event/code_parsing_posix_s_hell/ https://archive.fosdem.org/2018/schedule/event/code_parsing_...
- gavinhoward 2y ago
  The UX of the BNF notation. I am partial to hand-coded recursive descent purely because I struggled with Lex and Yacc too much when I tried.
  - chasil 2y ago
    I commiserate, it can be unforgiving, and the use of C is admittedly out of vogue.
    - gavinhoward 2y ago
      Oh, I love C. [1] But yes, unforgiving. And a lot of magic, with special variables, macros, and functions that you must know. And unclear scoping. [1]: https://gavinhoward.com/2023/02/why-i-use-c-when-i-believe-in-memory-safety/ https://gavinhoward.com/2023/02/why-i-use-c-when-i-believe-i...
      - kelnos 2y ago
        OT, but: I remember reading that post of yours a year or so ago! It was so bizarre to me, but also really fun. I feel like you are among what is probably a very small group of people who could write something security-sensitive in C, and I would feel comfortable using it. (I am still less than thrilled that I have to rely on OpenSSL, regardless of the process improvements its developer team has made in more recent years.) I still (unfortunately, IMO) write a lot of C. Back in 2004 I thought it was great fun. But now that I've worked in safer, batteries-included languages, I find C to be a huge drag. I'm so much more productive in Rust or even Java. I could never ever ever ever approach the level of rigor you bring to your C code; I just don't find doing all that stuff to be fun or interesting... to the contrary, it feels like a huge drag: if I were "required" to do all that, I just wouldn't write any code at all in C in the first place, knowing that having to do all the testing and fuzzing and static analysis stuff would burn me out. Anyhow, I hope I don't sound like I'm being critical... quite the opposite. I just think we live in a magnificent world where people's brains can work so so so differently when it comes to the same topic.
        gavinhoward 2y ago
        No offense taken; I know my brain is different. :) > I feel like you are among what is probably a very small group of people who could write something security-sensitive in C, and I would feel comfortable using it. This is probably the most complimentary thing anyone has ever said to me. Thank you! I hope I can live up to that.
nicoburns 2y ago
Are POSIX utilities even portable? They tend to have poor windows support. And they also tend to target C, which has a high ceiling for portability, but also a high bar for making things portable (whereas more modern languages are often just portable by default). My take on POSIX utilities would be only to use them on Linux platforms where they effectively form a "native" part of the platform.
- gavinhoward 2y ago
  I was mostly speaking about POSIX, since that was the focus of GGP. Yes, you should only use them on POSIX. My utility does build natively on Windows, though.
- chasil 2y ago
  The NT kernel was created with a POSIX layer (along with os/2). https://en.m.wikipedia.org/wiki/Microsoft_POSIX_subsystem https://en.m.wikipedia.org/wiki/Microsoft_POSIX_subsystem Microsoft had previously been the largest AT&T UNIX licensee with Xenix sales on the TRS-80 model 2, so they were familiar with the need.
- kelnos 2y ago
  > They tend to have poor windows support Does Windows claim POSIX compatibility these days? I didn't think so? I remember NT's old POSIX subsystem, but is that even a thing anymore? > My take on POSIX utilities would be only to use them on Linux platforms I mean, only use them on POSIX-compliant systems. Linux is just one of them. At the risk of sounding childishly derisive, when someone is talking about "portability", I think they're generally not bothering to include Windows in the mix, as Windows doesn't really share all that much of a common denominator with much else.
rnart 2y ago
I disagree here. The syntax can be infuriating at first, but once you understand it, Lex/Yacc are rock solid and speed up development significantly.

As the author of a POSIX standard utility, I would advise you to only reach for such utilities when portability is the most important thing. POSIX utilities are not great. Lex and Yacc included.

chasil 2y ago

Is your criticism of the relationship of the lexer and the parser, or something more fundamental? Is an LR parser expressed in BNF notation unsatisfactory? I say this only as it has been many years since I have written one, but I thought this OCaml presentation on a POSIX shell held the structure in high regard. https://archive.fosdem.org/2018/schedule/event/code_parsing_posix_s_hell/ https://archive.fosdem.org/2018/schedule/event/code_parsing_...

gavinhoward 2y ago
The UX of the BNF notation. I am partial to hand-coded recursive descent purely because I struggled with Lex and Yacc too much when I tried.
- chasil 2y ago
  I commiserate, it can be unforgiving, and the use of C is admittedly out of vogue.
  - gavinhoward 2y ago
    Oh, I love C. [1] But yes, unforgiving. And a lot of magic, with special variables, macros, and functions that you must know. And unclear scoping. [1]: https://gavinhoward.com/2023/02/why-i-use-c-when-i-believe-in-memory-safety/ https://gavinhoward.com/2023/02/why-i-use-c-when-i-believe-i...
    - kelnos 2y ago
      OT, but: I remember reading that post of yours a year or so ago! It was so bizarre to me, but also really fun. I feel like you are among what is probably a very small group of people who could write something security-sensitive in C, and I would feel comfortable using it. (I am still less than thrilled that I have to rely on OpenSSL, regardless of the process improvements its developer team has made in more recent years.) I still (unfortunately, IMO) write a lot of C. Back in 2004 I thought it was great fun. But now that I've worked in safer, batteries-included languages, I find C to be a huge drag. I'm so much more productive in Rust or even Java. I could never ever ever ever approach the level of rigor you bring to your C code; I just don't find doing all that stuff to be fun or interesting... to the contrary, it feels like a huge drag: if I were "required" to do all that, I just wouldn't write any code at all in C in the first place, knowing that having to do all the testing and fuzzing and static analysis stuff would burn me out. Anyhow, I hope I don't sound like I'm being critical... quite the opposite. I just think we live in a magnificent world where people's brains can work so so so differently when it comes to the same topic.
      - gavinhoward 2y ago
        No offense taken; I know my brain is different. :) > I feel like you are among what is probably a very small group of people who could write something security-sensitive in C, and I would feel comfortable using it. This is probably the most complimentary thing anyone has ever said to me. Thank you! I hope I can live up to that.

nicoburns 2y ago

Are POSIX utilities even portable? They tend to have poor windows support. And they also tend to target C, which has a high ceiling for portability, but also a high bar for making things portable (whereas more modern languages are often just portable by default). My take on POSIX utilities would be only to use them on Linux platforms where they effectively form a "native" part of the platform.

gavinhoward 2y ago
I was mostly speaking about POSIX, since that was the focus of GGP. Yes, you should only use them on POSIX. My utility does build natively on Windows, though.
chasil 2y ago
The NT kernel was created with a POSIX layer (along with os/2). https://en.m.wikipedia.org/wiki/Microsoft_POSIX_subsystem https://en.m.wikipedia.org/wiki/Microsoft_POSIX_subsystem Microsoft had previously been the largest AT&T UNIX licensee with Xenix sales on the TRS-80 model 2, so they were familiar with the need.
kelnos 2y ago
> They tend to have poor windows support Does Windows claim POSIX compatibility these days? I didn't think so? I remember NT's old POSIX subsystem, but is that even a thing anymore? > My take on POSIX utilities would be only to use them on Linux platforms I mean, only use them on POSIX-compliant systems. Linux is just one of them. At the risk of sounding childishly derisive, when someone is talking about "portability", I think they're generally not bothering to include Windows in the mix, as Windows doesn't really share all that much of a common denominator with much else.

rnart 2y ago

I disagree here. The syntax can be infuriating at first, but once you understand it, Lex/Yacc are rock solid and speed up development significantly.