Commands by Weboide (3)

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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

Fix Ubuntu's Broken Sound Server
Ever since the switch to pulseaudio, Ubuntu users including myself have found themselves with no sound intermittently. To fix this, just use this command and restarts firefox or mplayer or whatever.

Get the time from NIST.GOV
The format is JJJJJ YR-MO-DA HH:MM:SS TT L DUT1 msADV UTC(NIST) OTM and is explained more fully here: http://tf.nist.gov/service/acts.htm

Find removed files still in use via /proc
Oracle DBA remove some logfiles which are still open by the database and he is complaining the space has not been reclaimed? Use the above command to find out what PID needs to be stopped. Or alternatively recover the file via: $ cp /proc/pid/fd/filehandle /new/file.txt

Number file

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

Rename files in batch

Makes a Zenity select list based on entries in your wpa_supplicant.conf
If you still connect to your wireless access point manually and need to use wpa_supplicant, the above fu will grep all of the known SSID from your wpa_supplicant.conf file, present it in a Zenity list and return the SSID name you choose. I've wrapped this command in to a bash script that then up's the interface, associates and autenticates. Saves me from using NetworkManager ;)

Rename files in batch

Find where a kind of file is stored
In this case searches for where .desktop files are stored. The resulted is a sorted list of the top directories containing such files.


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