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Convert spaces in file names to underscores

A function to find the newest file in a directory

In place line numbering
Add permanent line numbers to a file without creating a temp file. The rm command deletes file10 while the nl command works on the open file descriptor of file10 which it outputs into a new file again named file10. The new file10 will now be numbered in the same directory with the same file name and content as before, but it will in fact be a new file, using (ls -i) to show its inode number will prove this.

Make .bashrc function to backup the data you changed last houres
The original overwrites any previous backups, and only saves exactly the last hours worth, but not 1 hour + 1 minute. This version creates or appends files, and backs up everything since the last backup (using the backups timestamp as the reference), plus it uses TMPDIR if set.

Get AWS temporary credentials ready to export based on a MFA virtual appliance
You might want to secure your AWS operations requiring to use a MFA token. But then to use API or tools, you need to pass credentials generated with a MFA token. This commands asks you for the MFA code and retrieves these credentials using AWS Cli. To print the exports, you can use: `awk '{ print "export AWS_ACCESS_KEY_ID=\"" $1 "\"\n" "export AWS_SECRET_ACCESS_KEY=\"" $2 "\"\n" "export AWS_SESSION_TOKEN=\"" $3 "\"" }'` You must adapt the command line to include: * $MFA_IDis ARN of the virtual MFA or serial number of the physical one * TTL for the credentials

Pipe the result of a command to IRC (channel or query)
$ command | my_irc Pipe whatever you want to this function, it will, if everything goes well, be redirected to a channel or a user on an IRC server. Please note that : - I am not responsible of flood excesses you might provoke. - that function does not reply to PINGs from the server. That's the reason why I first write in a temporary file. Indeed, I don't want to wait for inputs while being connected to the server. However, according to the configuration of the server and the length of your file, you may timeout before finishing. - Concerning the server, the variable content must be on the form "irc.server.org 6667" (or any other port). If you want to make some tests, you can also create a fake IRC server on "localhost 55555" by using $ netcat -l -p 55555 - Concerning the target, you can choose a channel (beginning with a '#' like "#chan") or a user (like "user") - The other variables have obvious names.

Replace strings in text
-e is the script function, it performs search and replace like vi, and -i is the edit the file in place.

get a rough estimate about how much disk space is used by all the currently installed debian packages
The vaule is expressed in megabytes

Use GNU info with a pager
This makes GNU info output menu items recursively and pipe its contents to less, allowing one to use GNU info in a manner similar to 'man'.

Find usb device in realtime
Using this command you can track a moment when usb device was attached.


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