FWIW AIX also has an apply command https://www.ibm.com/docs/en/aix/7.2?topic=apply-command
I spent a year using AIX at my previous job and never heard of this or saw anybody use it. Is it new in 7.2? We were far behind on AIX 6.
An Opinionated Guide to Xargs
81–90 of 135 posts
Re: An Opinionated Guide to Xargs
#82Earlier quoted context omitted.
Some additional tips: 1. You don't need the parentheses. 2. If you use process substitution [1] instead of a pipe, you will stay in the same process and can modify variables of the enclosing scope: i=0 while read -r v; do ... i=$(( i + 1)) done The drawback is that this way `do_something` has to come after `done`, but that's bash for you ¯\_(ツ)_/¯ [1] https://www.gnu.org/software/bash/manual/html_node/Process-S...
Yeah, although I use the parentheses mostly because I like how it reads. And that process substitution trick is important too. I think the redirection can come first, though (not at a computer to test):
This is not POSIX compliant though.
Re: An Opinionated Guide to Xargs
#83Of 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 ${unit}; done | ...
Re: An Opinionated Guide to Xargs
#84I appreciate this. If I wrote my own opinionated guide to xargs, it would be a single profane sentence.
Re: An Opinionated Guide to Xargs
#85[deleted]
Re: An Opinionated Guide to Xargs
#86I tend to reach for gnu parallel instead of xargs - https://www.gnu.org/software/parallel/parallel_alternatives.... parallel is probably on the complex side but its also been actively developed, bugfixed and had a lot of road miles from large computing users.
The nagware prompts of parallel are so objectionable that I will do a lot of things to avoid using it at all. So pretentious!
It's also written in Perl!
Re: An Opinionated Guide to Xargs
#87Earlier quoted context omitted.
I've been thinking about titles, and it's hard to make a good one that doesn't look like a total cliché. "X considered harmful", "an opinionated guide to X", some kind of joke or reference, what could be a collection of tags (X, Y and Z), "things I have learned doing X", etc.
I specifically clicked on this topic because of the word “opinionated”. As I already know how to use xargs, I was curious what kind of non-conventional or controversial opinion the author might have.
As I've said to a sibling comment, I don't think it's a bad title, and "an opinionated guide to X" is one of the better cliché for titles that I see (the worst being the journalist that feels like they have to make a joke).
Re: An Opinionated Guide to Xargs
#88FWIW AIX also has an apply command https://www.ibm.com/docs/en/aix/7.2?topic=apply-command
I spent a year using AIX at my previous job and never heard of this or saw anybody use it. Is it new in 7.2? We were far behind on AIX 6.
No idea how old this command is. Most of the AIX/Linux admins I knew were very bad shell programmers, skills end with awfull for-loops, useless use of cat, and awk '{print $3}'.
Re: An Opinionated Guide to Xargs
#89Since the blog author is commenting here, you have this statement part way down your blog: > That is, grep doesn't support an analogous -0 flag. However, the GNU grep variant does have an analogous flag: -z, --null-data Treat the input as a set of lines, each terminated by a zero byte (the ASCII NUL character) instead of a newline. Like the -Z or --null option, this option can be used with commands like sort -z to pr…
Ah cool, I didn't know that! I'll update the blog post. (What a cacophony of flags) Edit: It seems that grep -0 isn't taken for something else and they should have used it for consistency? The man page says it's meant to be used with find -print0, xargs -0, perl -0, and sort -z (another inconsistency)
It's best to give up on any kind of consistency between command options. Any project is free to do anything it wants, and they all do. Someone is eventually going to come up with standard N+1[1] which does things consistently, but they are going to have to either recreate a bazillion tools or create some sort of huge translation framework configuration on top of existing tools to get there. And even then it'll take literally decades before people migrate away from the current tools. Basically, the sad truth is this isn't going to happen.
Re: An Opinionated Guide to Xargs
#90I scanned until I saw `ls | egrep '.*_test\.(py|cc)' | xargs -d $'\n' -- rm`, and then stopped. This is a terrible idea[1][2].