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Comment by protomikron | Hacker News Reader

Interesting is also find. It took me some time to accept that the directory must come first.

E.g.

  find /path/to/dir -type f

works, while

  find -type f /path/to/dir

does not.

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Probably helps to think of find as its own weird pipeline rather than a command with options. The first element of the pipeline is the directory(/directories), then `-type f` filters out all the non-files, then `-name '*.txt'` filters out everything which doesn't end in ".txt", etc. That also helps to remember why `-maxdepth` has to be right after the directory; it affects which files even become part of the pipeline, it doesn't make sense as a pipeline element.

The clearest proof that it's a pipeline is probably how it interacts with `-exec`: `find . -type d -exec echo {} \;` will print only directories, while `find . -exec echo {} \; -type d` will print both files and directories.

Regardless though, I sure wish they would let you specify the directories at the end.

Very insightful, I never realized this. Thank you

I wrote a post about how to understand find syntax:

find and test: How To Read And Write Them

https://www.oilshell.org/blog/2021/04/find-test.html

tl;dr The args AFTER the root dir args form a boolean expression language -- I call it the "I'm too lazy to write a lexer" pattern

    find /tmp -type -f -a -name 'foo*'

test is the same way, e.g.

    test -f /tmp -a -f /bin

    find /tmp -type f -a -name 'foo*'  # no "-" for the -type

this is bitten me more often than I'd care to admit.

Oops, good point! Gah

I honestly wonder where this wonky syntax came from ... i.e. was it a Bell Labs thing or later

I just installed tesseract-ocr and it has a similar convention:

  tesseract imagename outputbase [options...] [configfile...]

Yup, always seems to take a bit more conscious effort to remember that detail for find.

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