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Bash: escape '-' character in filename
If you don't escape the - of the filename, you will get the command interpreting it as a parameter, returning (in the best case) an error.

Convert seconds to [DD:][HH:]MM:SS
Converts any number of seconds into days, hours, minutes and seconds. sec2dhms() { declare -i SS="$1" D=$(( SS / 86400 )) H=$(( SS % 86400 / 3600 )) M=$(( SS % 3600 / 60 )) S=$(( SS % 60 )) [ "$D" -gt 0 ] && echo -n "${D}:" [ "$H" -gt 0 ] && printf "%02g:" "$H" printf "%02g:%02g\n" "$M" "$S" }

change exif data in all jpeg's
this takes every jpg in the current directory and changes the exif data for manufactur and model. in my case i change it to LOMO LC-A because my scanner puts his data in there :]

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

Convert JSON to YAML
Convert JSON to YAML. Note that you'll need to have PyYaml installed.

reverse-i-search: Search through your command line history
"What it actually shows is going to be dependent on the commands you've previously entered. When you do this, bash looks for the last command that you entered that contains the substring "ls", in my case that was "lsof ...". If the command that bash finds is what you're looking for, just hit Enter to execute it. You can also edit the command to suit your current needs before executing it (use the left and right arrow keys to move through it). If you're looking for a different command, hit Ctrl+R again to find a matching command further back in the command history. You can also continue to type a longer substring to refine the search, since searching is incremental. Note that the substring you enter is searched for throughout the command, not just at the beginning of the command." - http://www.linuxjournal.com/content/using-bash-history-more-efficiently

Create the signature base string required for a Twitter stream feed
This is the SECOND command in a set for five that are needed for a Twitter stream feed. This command creates variable "b", the so-called "base string" required for oauth in Twitter stream feed requests. (The 256 char limit prevents giving it a better name) We use five environment variables created by a previous step: id, k1, once, ts and k3. The five environment variables are created in a separate command, please see my other commands. For more information on the signature base string, see dev.twitter.com/apps, click on any app (or create a new one) and then go to the "OAuth Tool" tab.

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.

List the size (in human readable form) of all sub folders from the current location

a shell function to print a ruler the width of the terminal window.
A similar version for Bash that doesn't require cut and shortens the function in a few places. And it uses local variables. (similar to a version by eightmillion in a comment on the another version)


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