Re: [PD] [command] can't execute "ls | wc -l"

[IOhannes m zmoelnig]

On 6/8/22 09:43, Alexandros wrote:

While [ggee/shell] outputs the correct number of files in a directory with the message "ls | wc -l", [command] outputs an error code 2 with "exec ls | wc -l" and doesn't output anything.

Is this intentional? If so, how can this command be executed by [command]?

probably by chaining up multiple [command]s?




a safer way would be to run
> find * -maxdepth 0 -type f  -exec printf . ";" | wc -c

but this is absymally slow (and still has the problem with the pipe).

a faster way would be to run this simple shell-script:
```sh
i=0
for f in *; do
  i=$((i+1))
done
echo $i
```

you can run this by creating a single symbol (without the quotes)
"i=0; for f in *; do i=$((i+1)); done; echo $i"




an even better way would be to just use [file glob]


fmgasdr
IOhannes


[1] http://mywiki.wooledge.org/ParsingLs

but more importantly: "ls | wc -l" is an anti-pattern: you shouldn't parse the output of `ls` [1] e.g. your script breaks as soon as your directory contains files with a newline in their name. and then send a message "exec bash -c $1" (with $1 replaced by the symbol) to [command]. this will launch a full-fledged bash that will then interpret your little script.

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