### All commands (14,086) the last day the last week the last month all time sorted by date votes

• Convert Windows/DOS Text Files to Uni Show Sample Output

-26
Convert Windows/DOS Text Files to Uni
· 2009-10-24 18:41:35

• -26
w3m
· 2009-02-20 07:22:07

• -27
perl -e 'print "Hello World!", "\n";'
· 2009-03-24 14:58:01
• This command install Apache 2 and other utilities on CentOS

-31
yum install httpd
· 2009-02-19 16:59:51
• I am using .bat commands to execute Curl commands for Twitter API Show Sample Output

-34
test.bat parm1 parm2 parm3
· 2009-03-25 12:27:18
• Useful to quickly get back to the Windows root directory of the current drive from a sub-directory within that drive. Works also without space between 'cd' and backslash: 'cd\' or 'cd \' have the same effect Show Sample Output

-35
cd \
· 2009-02-14 21:53:51

• -44
ipconfig /all
· 2009-03-06 17:36:07

• -74
· 2009-11-09 20:26:50
• EDIT: Trolling crap removed ;) takes approx 6 secs on a Core 2 Duo @ 2GHz, and 15 secs on atom based netbooks! uses monoid (a,b).(x,y)=(ax+bx+ay,ax+by) with identity (0,1), and recursion relations: F(2n-1)=Fn*Fn+F(n-1)*F(n-1) F(2n)=(Fn+2*F(n-1))*Fn then apply fast exponentiation to (1,0)^n = (Fn,F(n-1)) . Note that: (1,0)^-1=(1,-1) so (a,b).(1,0) = (a+b,a) and (a,b)/(1,0)=(a,b).(1,0)^-1=(b,a-b) So we can also use a NAF representation to do the exponentiation,http://en.wikipedia.org/wiki/Non-adjacent_form , it's also very fast (about the same, depends on n): `time echo 'n=1000000;m=(n+1)/2;a=0;b=1;i=0;while(m>0){z=0;if(m%2)z=2-(m%4);m=(m-z)/2;e[i++]=z};while(i--){c=a*a;a=c+2*a*b;b=c+b*b;if(e[i]>0){t=a;a+=b;b=t};if(e[i]<0){t=a;a=b;b=t-b}};if(n%2)a*a+b*b;if(!n%2)a*(a+2*b)' | bc` Show Sample Output

-135
time echo 'n=1000000;m=(n+1)/2;a=0;b=1;i=0;while(m){e[i++]=m%2;m/=2};while(i--){c=a*a;a=c+2*a*b;b=c+b*b;if(e[i]){t=a;a+=b;b=t}};if(n%2)a*a+b*b;if(!n%2)a*(a+2*b)' | bc
· 2009-09-10 09:00:44
• Calculates nth Fibonacci number for all n>=0, (much faster than matrix power algorithm from http://everything2.com/title/Compute+Fibonacci+numbers+FAST%2521 ) n=70332 is the biggest value at http://bigprimes.net/archive/fibonacci/ (corresponds to n=70331 there), this calculates it in less than a second, even on a netbook. UPDATE: Now even faster! Uses recurrence relation for F(2n), see http://en.wikipedia.org/wiki/Fibonacci_number#Matrix_form n is now adjusted to match Fn at wikipedia, so bigprimes.net table is offset by 1. UPDATE2: Probably fastest possible now ;), uses a simple monoid operation: uses monoid (a,b).(x,y)=(ax+bx+ay,ax+by) with identity (0,1), and recursion relations: F(2n-1)=Fn*Fn+F(n-1)*F(n-1) F(2n)=Fn*(2*F(n-1)+Fn) then apply fast exponentiation to (1,0)^n = (Fn,F(n-1)) . Note that: (1,0)^-1=(1,-1) so (a,b).(1,0) = (a+b,a) and (a,b)/(1,0)=(a,b).(1,0)^-1=(b,a-b) So we can also use a NAF representation to do the exponentiation,http://en.wikipedia.org/wiki/Non-adjacent_form , it's also very fast (about the same, depends on n): `time echo 'n=70332;m=(n+1)/2;a=0;b=1;i=0;while(m>0){z=0;if(m%2)z=2-(m%4);m=(m-z)/2;e[i++]=z};while(i--){c=a*a;a=c+2*a*b;b=c+b*b;if(e[i]>0){t=a;a+=b;b=t};if(e[i]<0){t=a;a=b;b=t-b}};if(n%2)a*a+b*b;if(!n%2)a*(a+2*b)' | bc` Show Sample Output

-136
time echo 'n=70332;m=(n+1)/2;a=0;b=1;i=0;while(m){e[i++]=m%2;m/=2};while(i--){c=a*a;a=c+2*a*b;b=c+b*b;if(e[i]){t=a;a+=b;b=t}};if(n%2)a*a+b*b;if(!n%2)a*(a+2*b)' | bc
· 2009-09-10 08:58:47
• The end of unix time and the 32bit era will be Tue Jan 19 03:14:07 UTC 2038 . `date -ud @\$[2**31]` date: invalid date `@2147483648' . In 64bit you have much longer, at least to: `date -ud @\$[2**55]` `Sun Jun 13 06:26:08 UTC 1141709097` Show Sample Output

-149
date -ud @\$[2**31-1]
· 2009-09-11 08:48:50
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list block devices
Shows all block devices in a tree with descruptions of what they are.

Blink Caps Lock on HDD activity
Some computers these days don't have an HDD activity light, but they still have a useless caps-lock, so why not re-purpose that light to show HDD activity? Requires setleds and dstat and probably needs to run as root.

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"

Tree based ps view "painted" by ccze

Find jpeg images and copy them to a central location
Use if you have pictures all over the place and you want to copy them to a central location Synopsis: Find jpg files translate all file names to lowercase backup existing, don't overwrite, preserve mode ownership and timestamps copy to a central location

Convert seconds to [DD:][HH:]MM:SS
Converts any number of seconds into days, hours, minutes and seconds. sec2dhms() { declare -i SS="\$1" D=\$(( SS / 86400 )) H=\$(( SS % 86400 / 3600 )) M=\$(( SS % 3600 / 60 )) S=\$(( SS % 60 )) [ "\$D" -gt 0 ] && echo -n "\${D}:" [ "\$H" -gt 0 ] && printf "%02g:" "\$H" printf "%02g:%02g\n" "\$M" "\$S" }

Convert seconds to [DD:][HH:]MM:SS
Converts any number of seconds into days, hours, minutes and seconds. sec2dhms() { declare -i SS="\$1" D=\$(( SS / 86400 )) H=\$(( SS % 86400 / 3600 )) M=\$(( SS % 3600 / 60 )) S=\$(( SS % 60 )) [ "\$D" -gt 0 ] && echo -n "\${D}:" [ "\$H" -gt 0 ] && printf "%02g:" "\$H" printf "%02g:%02g\n" "\$M" "\$S" }

Increase SCT of external USB disk enclosure to one hour.
So I had this 2TB Seagate external disk/USB enclosure which by default would spin-down its internal drive (it enters a standby mode) after four minutes of inactivity.. Spinning-up the inactive drive was an annoying delay when accessing files and also it severely interfered with NFS.. SCT stands for "Standby Condition Timer". To completely disable SCT: \$ sdparm --clear STANDBY -6 /dev/sdb To return to original (default) SCT settings: \$ sdparm -D -p 0x1a -6 /dev/sdb To verify the settings (before and after): \$ sdparm -a /dev/sdb No need for vendor-provided MSWIN tools, etc.

Check reverse DNS
I'm just a simple programmer. I find dig too verbose. host tells me alias(es) and IP address in a quick to grok format with nothing special to remember for input parameters. With thanks to http://www.cyberciti.biz/faq/how-to-test-or-check-reverse-dns/

String to binary
Cool but useless.

### Stay in the loop…  