Commands by wipu

Commands by wipu (4)

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Suppress output of loud commands you don't want to hear from

This works even if there are spaces in any word in the command line. Show Sample Output
This is sample output - yours may be different.
```
quietly "/path that may contain spaces/command" "arg 1" "arg 2"
```
3

quietly() { "$@" > /dev/null 2>&1; }

wipu · 2011-10-04 06:45:42 1
Reproduce test failure by running the test in loop

If you need to fix a randomly failing test (race condition), you need to run it until you get that hard-to-reproduce failure. Show Sample Output
This is sample output - yours may be different.
```
Test run starting...
...
SUCCESS
Test run starting...
...
FAILURE
```
-3

(set -e; while true; do TEST_COMMAND; done) | tee log

wipu · 2011-09-06 12:29:11 0
Sum size of files returned from FIND

Just an alternative. Here the output of the subshell statement is a complete script for dc so you can save it, manipulate it with some other tool or just debug it with less.
This is sample output - yours may be different.
0

(echo 0; find [args...] -printf '%s +\n'; echo p) | dc

wipu · 2011-08-17 07:49:55 1
Robust expansion (i.e. crash) of bash variables with a typo

By default bash expands an unbound variable to an empty string. This can be dangerous, if a critical variable name (a path prefix for example) has a typo. The -u option causes bash to treat this as an error, and the -e option causes it to exit in case of an error. These two together will make your scripts a lot safer against typos. The default behaviour can be explicitly requested using the ${NAME:-} syntax. A (less explicit) variation: #!/bin/bash -eu Show Sample Output
This is sample output - yours may be different.
```
$ cat safe-cacheclean.sh 
#!/bin/bash

set -eu
CACHEDIR=mycache
# a dangerous-looking typo, is /bin going to disappear:
rm -rf "$CACHEDI/bin"

$ ./safe-cacheclean.sh 
./safe-cacheclean.sh: line 7: CACHEDI: unbound variable
```
8

set -eu

wipu · 2010-04-07 11:54:40 2

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Convert CSV to JSON

Replace 'csv_file.csv' with your filename.

Detect illegal access to kernel space, potentially useful for Meltdown detection

Based on capsule8 agent examples, not rigorously tested

shuffle lines via bash

Using perl in a one-liner is a bit overkill to randomly sort some input. `sort` from coreutils should be enough.

Convert files from DOS line endings to UNIX line endings

This method will also convert mac line endings.

recursively walk down no more than three levels and grab any file with an extension of mp3, mpg, mpeg, or avi

Print all git repos from a user

in case you could afford installing jq

Uptime in minute

Listing today’s files only

list block devices

Shows all block devices in a tree with descruptions of what they are.

Find the package that installed a command

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Commands by wipu (4)

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