Commands by d3Xt3r (3)

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Insert a line at the top of a text file without sed or awk or bash loops
Yet another way to add a line at the top a of text file with the help of the tac command (reverse cat).

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

creeate file named after actual date
Create a file with actual date as filename

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

Display text as though it is being typed out in real time
Pipe Viewer allows you to monitor the progress of a data transfer or command, or to show the time elapsed, among other things. In this use, it limits the transfer rate of the echo command to 10 bytes per second, making your text appear to be typed out in real time as in Hollywood movies. Fun!

lsof equivalent on solaris
Report fstat(2) and fcntl(2) information for all open files in each process.

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

Advanced LS Output using Find for Formatted/Sortable File Stat info
I love this function because it tells me everything I want to know about files, more than stat, more than ls. It's very useful and infinitely expandable. $ find $PWD -maxdepth 1 -printf '%.5m %10M %#9u:%-9g %#5U:%-5G [%AD | %TD | %CD] [%Y] %p\n' | sort -rgbS 50% 00761 drwxrw---x askapache:askapache 777:666 [06/10/10 | 06/10/10 | 06/10/10] [d] /web/cg/tmp The key is: # -printf '%.5m %10M %#9u:%-9g %#5U:%-5G [%AD | %TD | %CD] [%Y] %p\n' which believe it or not took me hundreds of tweaking before I was happy with the output. You can easily use this within a function to do whatever you want.. This simple function works recursively if you call it with -r as an argument, and sorts by file permissions. $ lsl(){ O="-maxdepth 1";sed -n '/-r/!Q1'

find the biggest file in current folder

Get contents from hosts, passwd, groups even if they're in DB/LDAP/other
getent allows to get the contents of several databases in their native file format even if they are not actually in /etc. For example, if you are using a LDAP or a DB to authenticate your users, you won't find their info by catting /etc/passwd, but "getent passwd" will concatenate /etc/passwd to the LDAP/DB.


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