Commands tagged jpg (12)

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Simplified video file renaming
I used this when I had a directory of movies from a camera. I wanted to watch a little of each movie, then rename it depending on what was in the movie. This did the trick for me.

Random Number Between 1 And X
If X is 5, it will about a number between 1 and 5 inclusive. This works in bash and zsh. If you want between 0 and 4, remove the +1.

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"

Runs a command without hangups.
puts command in background and sends its output to nohup.out file it will not die if you log out fromyour shell session ;-)

Print text string vertically, one character per line.

Opens files containing search term in vim with search term highlighted
Takes the same arguments that ack does. E.g. ack-open -i "searchterm" opens all files below the current directory containing the search term. The search term is also highlighted within vim if you have hlsearch set. Works on zsh, unsure if it works on bash. Note: ubuntu users have to change ack to ack-grep unless you already have it aliased (as I do)

Print every Nth line
Sometimes commands give you too much feedback. Perhaps 1/100th might be enough. If so, every() is for you. $ my_verbose_command | every 100 will print every 100th line of output. Specifically, it will print lines 100, 200, 300, etc If you use a negative argument it will print the *first* of a block, $ my_verbose_command | every -100 It will print lines 1, 101, 201, 301, etc The function wraps up this useful sed snippet: $ ... | sed -n '0~100p' don't print anything by default $ sed -n starting at line 0, then every hundred lines ( ~100 ) print. $ '0~100p' There's also some bash magic to test if the number is negative: we want character 0, length 1, of variable N. $ ${N:0:1} If it *is* negative, strip off the first character ${N:1} is character 1 onwards (second actual character).

Use Perl like grep
If you've ever tried "grep -P" you know how terrible it is. Even the man page describes it as "highly experimental". This function will let you 'grep' pipes and files using Perl syntax for regular expressions. The first argument is the pattern, e.g. '/foo/'. The second argument is a filename (optional).

a simple bash one-liner to create php file and call php function

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"


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