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pdfunite is a part of the poppler-utils. poppler-utils package is only 150KB. The alternative - pdftk package is 14MB! Install poppler-utils if you need simple pdf operation commands like unite, separate, info, text/html conversions
Do it.
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"
Found here: http://ubuntuforums.org/showthread.php?t=589975
Each shell function has its own summary line, as a comment. If there are multiple shell functions with the same name, the function with the highest number of votes is put into the file.
Note: added 'grep -v' to the end of the pipeline, to eliminate extraneous lines containing only '--'. Thanks to matthewbauer for pointing this out.
Sometimes in a script you want to make sure that a directory is in the path, and add it in if it's not already there. In this example, $dir contains the new directory you want to add to the path if it's not already present.
There are multiple ways to do this, but this one is a nice clean shell-internal approach. I based it on http://stackoverflow.com/a/1397020.
You can also do it using tr to separate the path into lines and grep -x to look for exact matches, like this:
$ if ! $(echo "$PATH" | tr ":" "\n" | grep -qx "$dir") ; then PATH=$PATH:$dir ; fi
which I got from http://stackoverflow.com/a/5048977.
Or replace the "echo | tr" part with a shell parameter expansion, like
$ if ! $(echo "${PATH//:/$'\n'}" | grep -qx "$dir") ; then PATH=$PATH:$dir ; fi
which I got from http://www.commandlinefu.com/commands/view/3209/.
There are also other more regex-y ways to do it, but I find the ones listed here easiest to follow.
Note some of this is specific to the bash shell.
watch is a command especially designed for doing this job
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.