Commands by speaker

Commands by speaker (2)

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Test if the given argument is a valid ip address.

This command will output 1 if the given argument is a valid ip address and 0 if it is not. Show Sample Output
This is sample output - yours may be different.
```
1
```
0

perl -e '$p=qr!(?:0|1\d{0,2}|2(?:[0-4]\d?|5[0-5]?|[6-9])?|[3-9]\d?)!;print((shift=~m/^$p\.$p\.$p\.$p$/)?1:0);' 123.123.123.123

speaker · 2009-07-12 00:24:29 3
Outputs files with ascii art in the intended form.

Files containing ascii art (e.g. with .nfo extension) are typically not correctly reproduced at the command line when using cat. With iconv one can easily write a wrapper to solve this: #!/bin/bash if [ -z "$@" ]; then echo "Usage: $(basename $0) file [file] ..." else iconv -f437 -tutf8 "$@"; fi exit 0
This is sample output - yours may be different.
9

iconv -f437 -tutf8 asciiart.nfo

speaker · 2009-07-11 23:50:05 8

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Convert CSV to JSON

Replace 'csv_file.csv' with your filename.

Synchronize both your system clock and hardware clock and calculate/adjust time drift

Do not run this command if you already have ntpd running! This needs to run as root, for example with sudo: $ sudo ntpdate pool.ntp.org && sudo hwclock --systohc && sudo hwclock --adjust This command will fetch accurate time from NTP servers and synchronize your system clock, then it will use the system clock to synchronize your hardware clock, and will calculate the time drift.

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Exit mc with 2 keystrokes

For those who like to hit instead of typing "exit" to leave the shell and find it annoying that it doesn't work in Midnight Commander, just press to switch to the subshell and now you can leave with

list block devices

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

Batch convert PNG to JPEG

Convert all PNG images in directory to JPEG using ImageMagick, and delete the old PNG images.

dd with progress bar and statistics to gzipped image

Install pip with Proxy

Installs pip packages defining a proxy

Use mtr to create a text file report

The report mode of mtr produces a text formated result of the mtr run using the number of ping cycles stated by the command. This text file could then be attached to an email with ease. I use this also without the ">" portion when writing email from within mutt using VI from the command mode with ":r !mtr --report --report-cycles 10 www.google.com" to actually input the same output in the body of an email.

Benchmark SQL Query

Benchmark a SQL query against MySQL Server. The example runs the query 10 times, and you get the average runtime in the output. To ensure that the query does not get cached, use `RESET QUERY CACHE;` on top in the query file.

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