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Add a progress counter to loop (see sample output)
For this hack you need following function: $ finit() { count=$#; current=1; for i in "$@" ; do echo $current $count; echo $i; current=$((current + 1)); done; } and alias: $ alias fnext='read cur total && echo -n "[$cur/$total] " && read' Inspired by CMake progress counters.

back ssh from firewalled hosts
host B (you) redirects a modem port (62220) to his local ssh. host A is a remote machine (the ones that issues the ssh cmd). once connected port 5497 is in listening mode on host B. host B just do a ssh 127.0.0.1 -p 5497 -l user and reaches the remote host'ssh. This can be used also for vnc and so on.

Kill all processes that listen to ports begin with 50 (50, 50x, 50xxx,...)
Run netstat as root (via sudo) to get the ID of the process listening on the desired socket. Use awk to 1) match the entry that is the listening socket, 2) matching the exact port (bounded by leading colon and end of column), 3) remove the trailing slash and process name from the last column, and finally 4) use the system(…) command to call kill to terminate the process. Two direct commands, netstat & awk, and one forked call to kill. This does kill the specific port instead of any port that starts with 50. I consider this to be safer.

enumerate with padding
bash2 : for X in $(seq 1 5); do printf "%03g " "$X";done bash3 : for X in {1..5}; do printf "%03g " "$X";done bash4 : echo {001..5}

Most simple way to get a list of open ports

count processes with status "D" uninterruptible sleep

which program is this port belongs to ?
Sometimes you need to use a port that is already opened by some program , and you don't know who to "kill" for it to release - so, now you do !

create shortcut keys in bash

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"

execute your commands and avoid history records
Sometimes you don't want to leave history, because of passwords use or somethink like. I think it help.


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