Commands by slashdot (6)

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Make vim open in tabs by default (save to .profile)
I always add this to my .profile rc so I can do things like: "vim *.c" and the files are opened in tabs.

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" }

Displays the version of the Adobe Flash plugin installed
This is for Debian, simply change the path if your Flash plugin is installed elsewhere.

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

Function to split a string into an array

Test speaker channels
Useful tool to test if all speaker channels are working properly. speaker-test is part of alsa-utils package

Exclude inserting a table from a sql import
Starting with a large MySQL dump file (*.sql) remove any lines that have inserts for the specified table. Sometimes one or two tables are very large and uneeded, eg. log tables. To exclude multiple tables you can get fancy with sed, or just run the command again on subsequently generated files.

preprocess code to be posted in comments on this site
Assuming that $script contains the filename of a script you'd like to post as part of a comment on this site, this will prefix each line with '$' and pipe it into the X selection. From there just put the cursor in the right place in the comments box and middle-click. Should work pretty much anywhere with xclip installed. On debian-ish systems this is installed as part of the package "xclip".

Show the total number of changes that every user committed to a Subversion repository
This saves Subversion's log output as XML and then runs an XQuery over it. This is standard XQuery 1.0 and should therefore also work with other XQuery processors. I have tested it with Zorba (http://www.zorba-xquery.com). XQilla (http://xqilla.sourceforge.net) also does it, but you'd have to save the query to a file and then execute "xqilla filename.xq". The query first finds all distinct authors and then, for each author, sums up the number of paths they have changed in each commit. This accounts for commits of multiple changes at once. The indenting space in all lines from the second one seems to be due to a bug in Zorba.

all out
How to force a userid to log out of a Linux host, by killing all processes owned by the user, including login shells:


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