Commands tagged grep (409)

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Find Duplicate Files (based on MD5 hash) -- For Mac OS X
This works on Mac OS X using the `md5` command instead of `md5sum`, which works similarly, but has a different output format. Note that this only prints the name of the duplicates, not the original file. This is handy because you can add `| xargs rm` to the end of the command to delete all the duplicates while leaving the original.

Clean the /boot directory
On Fedora clean the boot directory; erase older kernel

show the working directories of running processes
this shows the CWD of every running `java' command. YMMV but we often switch to a working directory for each service to start and run from there -- therefore this quicly shows what is running by a more meaningful name than command alone (the -bw prevents using blocking system calls which speeds this up quite a bit in the presence of remote mounted filesystems)

Automatically find and re-attach to a detached screen session
man screen: "-D -R Attach here and now. In detail this means: If a session is running, then reattach. If necessary detach and logout remotely first. If it was not running create it and notify the user. This is the author?s favorite."

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" }

Find default gateway

Perl One Liner to Generate a Random IP Address
A bash version.

Check ps output to see if file is running, if not start it
This comes in handy if you have daemons/programs that have potential issues and stop/disappear, etc., can be run in cron to ensure that a program remains up no matter what. Be advised though, if a program did core out, you'd likely want to know why (gdb) so use with caution on production machines.

Convert ascii string to hex
If you're going to use od, here's how to suppress the labels at the beginning. Also, it doesn't output the \x, hence the sed command at the end. Remove it for space separated hex values instead

extract all urls from firefox sessionstore
This will extract all of the urls from a firefox session (including urls in a tab's history). The sessionstore.js file is in ~/.mozilla/firefox/{firefox profile}


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