Commands by skkzsh (5)

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Replace all in last command

list files recursively by size

Update program providing a functionality on Debian
On Debian systems, choose which command provides java. Works for all alternatives listed in /etc/alternatives.

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

Use a Gmail virtual disk (GmailFS) on Ubuntu
Packages: gmailfs fuse-utils libfuse2 gvfs-fuse Config files: /etc/gmailfs/gmailfs.conf; ~/.gmailfs.conf (make a copy from the another one) Unmount: $ fusermount -u /mount/path/ /etc/fstab (Optional): none /mount/path/ gmailfs noauto,user[,username=USERNAME,password=PASSWORD,fsname=VOLUME] 0 0 NOTES: - The options between [] are optional since they already setuped on the config files. - The '-p' flag shows a prompt for the password entry. - It's necessary to add the user to the 'fuse' group. You can do that with: $ sudo chgrp fuse /dev/fuse and $ sudo usermod -a -G fuse USER - The volume name is not needed but highly recommended to avoid file corruption. Also choose a non-trivial name. - Google doesn't approve the use of Gmail account other than e-mail purposes. So, I recommend the creation of a new account for this.

Function to output an ASCII character given its decimal equivalent
I've corrected the function. My octal conversion formula was completely wrong. Thanks to pgas at http://mywiki.wooledge.org/BashFAQ/071 for setting me straight. The new function is from pgas and is very fast.

reduce mp3 bitrate (and size, of course)
Useful if you have to put some mp3 files into mobile devices (ie mobile phones with no much memory)

one-line log format for svn
the output of svn log is annoying to grep, since it spreads the useful info over multiple lines. This compacts the output down to one line so eg you can grep for a comment and see the rev, date & committer straight away. Updated: MUCH shorter, easier to remember. Now it just replaces newlines with spaces, except on '---' lines.

Find Duplicate Files (based on size first, then MD5 hash)
Finds duplicates based on MD5 sum. Compares only files with the same size. Performance improvements on: $find -not -empty -type f -printf "%s\n" | sort -rn | uniq -d | xargs -I{} -n1 find -type f -size {}c -print0 | xargs -0 md5sum | sort | uniq -w32 --all-repeated=separate The new version takes around 3 seconds where the old version took around 17 minutes. The bottle neck in the old command was the second find. It searches for the files with the specified file size. The new version keeps the file path and size from the beginning.

Convert CSV to JSON
Replace 'csv_file.csv' with your filename.


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