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Comment by yudlejoza | Hacker News Reader

Of xargs, for, and while, I have limited myself to while. It's more typing everytime but saves me from having to remember so many quirks of each command.

    cat input.file | ... | while read -r unit; do <cmd> ${unit}; done | ...

between 'while read -r unit' and 'while IFS= read -r unit' I can probably handle 90% of the cases. (maybe I should always use IFS since I tend to forget the proper way to use it).

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That way will bite you when the tasks in question are cheaper than fork+exec. There was a thread just the other day in which folks were creating 8 million empty files with a bash loop over touch. But it's 60X faster (really, I measured) to use xargs, which will do batches (and parallelism if you tell it to).

https://news.ycombinator.com/item?id=28192946

Would you mind expanding with a couple of examples? (E.g. using "foo bar" as a single line or split by whitespace).

I suspect I'll really like your way of doing things, but an example would be very handy.

The example of "foo bar" didn't work with while but inserting tr fixes it:

    echo "foo bar" | tr ' ' '\n' | while read -r var; do echo ${var}; done

For examples in general, I guess something like "cat file.csv" could work. (the difference between using IFS= and not using it is essentially whether we want to preserve leading and trailing whitespaces or not. If we want to preserve, then we should use IFS=).

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