Shell Tricks That Make Life Easier (and Save Your Sanity)

https://blog.hofstede.it/shell-tricks-that-actually-make-life-easier-and-save-your-sanity/

#HackerNews #ShellTricks #LifeHacks #Productivity #TechTips #SanitySaver

Sometimes zip files are rude and don't have a top directory. Here's a one-liner to unzip a bunch of archives into directories named after each file:

```
for f in *.zip; do unzip -d ${f/.zip/} $f; done
```

#bashTricks #shTricks #shellTricks

Bash has a way to specify strings with escaped characters like so: $'\r\n' which gives a string containing carriage return and newline characters.

The `read` built-in can take a delimiter with the -d flag. Combining these lets you use a null character: read -d $'\0'

Useful in some of the same places you might use xargs(1).

find . -name ... -print0 | while read -d $'\0'; do ./foo "$REPLY"; done

#bashTricks #xargs #bash #shellTricks

A common parsing task is finding lines that match a pattern but only if another pattern is seen first.

The MacOS utility otool(1) prints the load commands in a Mach-O binary with a header line followed by the info about that load command on several subsequent lines.

This one liner will show just the path for every imported dylib:

otool -l foo
| awk '/LC_LOAD_DYLIB/{ in_dylib_lc=1 }; in_dylib_lc == 1 && /name/ { in_dylib_lc = 0; print }'

#bashTricks #awk #shellTricks

Capture STDOUT, STDERR and return status in shell variables

This second answer ( the one with the banana function ) shows how to capture all three to variables in bash without needing tmp files

https://stackoverflow.com/questions/13806626/capture-both-stdout-and-stderr-in-bash

----
banana() {
echo "banana to stdout"
echo >&2 "banana to stderr"
return 42
}
----

----
. <({ berr=$({ bout=$(banana); bret=$?; } 2>&1; declare -p bout bret >&2); declare -p berr; } 2>&1)
----

Then check values of $bout, $berr, $bret

#ShellTricks #bash #FLOX