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Commands by flatcap from sorted by
Terminal - Commands by flatcap - 33 results
rf() { for i in "$@"; do mv "$i" "$(pwgen 8 1).${i##*.}"; done }
2011-06-22 07:45:23
User: flatcap
Functions: mv
1

Give files a random name (don't ask why :-)

The function will rename files but maintain their extensions.

BUG: If a file doesn't have an extension it will end up with a dot at the end of the name.

The parameter '8' for pwgen controls the length of filenames - eight random characters.

find . -type f -name \*.php | while IFS="" read i; do expand -t4 "$i" > "$i-"; mv "$i-" "$i"; done
2011-04-08 12:53:14
User: flatcap
Functions: expand find mv read
-4

Recursively find php files and replace tab characters with spaces.

Options:

"\*.php" -- replace this with the files you wish to find

"expand" -- replace tabs with spaces (use "unexpand" to replace spaces with tabs)

"-t4" -- tabs represent 4 spaces

Note: The IFS="" in the middle is to prevent 'read' from eating leading/trailing whitespace in filenames.

ls -1 | sort -R | sed -n 's/^/Selected /;1p'
MIN=10;for ((i=MIN*60;i>=0;i--));do echo -ne "\r$(date -d"0+$i sec" +%H:%M:%S)";sleep 1;done
2011-02-20 11:56:28
User: flatcap
Functions: echo sleep
11

Countdown clock - Counts down from $MIN minutes to zero.

I let the date command do the maths.

This version doesn't use seq.

s(){ sed 's/./\n\0/g'<<<$1|sort;};cmp -s <(s foobar) <(s farboo)||echo -n "not ";echo anagram
2011-02-17 12:42:45
User: flatcap
Functions: cmp echo sed
-3

Are the two strings anagrams of one another?

sed splits up the strings into one character per line

the result is sorted

cmp compares the results

Note: This is not pretty. I just wanted to see if I could do it in bash.

Note: It uses fewer characters than the perl version :-)

files -type f | xargs -n100 | while read l; do mkdir $((++f)); cp $l $f; done
2011-02-15 23:15:16
User: flatcap
Functions: cp mkdir read xargs
-2

Take a folder full of files and split it into smaller folders containing a maximum number of files. In this case, 100 files per directory.

find creates the list of files

xargs breaks up the list into groups of 100

for each group, create a directory and copy in the files

Note: This command won't work if there is whitespace in the filenames (but then again, neither do the alternative commands :-)

for((r=1;r<10;r++));do v=1;echo -n "$v ";for((c=1;c<$r;c++));do v2=$(($(echo "$v*($r-$c)/$c")));echo -n "$v2 ";v=$v2;done;echo;done
2011-02-10 18:38:04
User: flatcap
Functions: echo
Tags: bash math
0

http://en.wikipedia.org/wiki/Pascal%27s_triangle

This one's for bartonski. Enjoy.

132 characters. I'm sure we can do better.

Note: after row 64 we overflow integer maths.

seq 1 2 99999999 | sed 's!^!4/!' | paste -sd-+ | bc -l
2011-02-09 23:36:07
User: flatcap
Functions: bc paste sed seq
Tags: sed seq bc paste math
0

Calculate pi from the infinite series 4/1 - 4/3 + 4/5 - 4/7 + ...

This expansion was formulated by Gottfried Leibniz: http://en.wikipedia.org/wiki/Leibniz_formula_for_pi

I helped rubenmoran create the sum of a sequence of numbers and he replied with a command for the sequence: 1 + 2 -3 + 4 ...

This set me thinking. Transcendental numbers!

seq provides the odd numbers 1, 3, 5

sed turns them into 4/1 4/3 4/5

paste inserts - and +

bc -l does the calculation

Note: 100 million iterations takes quite a while. 1 billion and I run out of memory.