Commands by axelabs

Commands by axelabs (11)

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Use the builtin ':' bash command to increment variables

I just found another use for the builtin ':' bash command. It increments counters for me in a loop if a certain condition is met... : [arguments] No effect; the command does nothing beyond expanding arguments and performing any specified redirections. A zero exit code is returned. Show Sample Output
This is sample output - yours may be different.
```
1
```
2

[ $V ] || : $((V++)) && echo $V

axelabs · 2012-06-15 16:48:03 0
Synchronize directory copy

rsync will copy the source directory into destination and any subsequent run will synchronize only the changes from the source. Show Sample Output
This is sample output - yours may be different.
```
building file list ... done
src/
src/modified
src/newfile

sent 271 bytes  received 70 bytes  682.00 bytes/sec
total size is 30  speedup is 0.09
```
0

rsync -avz ~/src ~/des/

axelabs · 2012-06-01 15:08:12 2
Time conversion/format using the date command

Show Sample Output
This is sample output - yours may be different.
```
epoch: 1323946029 or format: 2011/12/15
```
1

date -d '2011-12-15 05:47:09' +"epoch: %s or format: %Y/%m/%d"

axelabs · 2011-12-16 18:43:36 0
Identifying Xorg video driver in use

The above one liner can be used to determine what card/driver is Xorg currently using. For additional information, see http://goo.gl/mDnWu Show Sample Output
This is sample output - yours may be different.
```
[    27.597] (II) RADEON(0): PCIE card detected
[    27.638] (II) RADEON(0): Output LVDS connected
```
-1

egrep -i " connected|card detect|primary dev" /var/log/Xorg.0.log

axelabs · 2011-02-24 18:04:04 0
Use tee to process a pipe with two or more processes

Tee can be used to split a pipe into multiple streams for one or more process to work it. You can add more " >()" for even more fun. Show Sample Output
This is sample output - yours may be different.
```
tee can split a pipe in two
tee_can_split_a_pipe_in_two
owt ni epip a tilps nac eet
```
33

echo "tee can split a pipe in two"|tee >(rev) >(tr ' ' '_')

axelabs · 2010-08-14 20:38:59 3
Sed can refference parts of the pattern in the replacement:

Show Sample Output
This is sample output - yours may be different.
```
me=swap
2=1
```
2

echo -e "swap=me\n1=2"|sed 's/$.*$=$.*$/\2=\1/g'

axelabs · 2010-01-16 22:01:37 0
Watch number of lines being processed on a clear screen

awk can clear the screen while displaying output. This is a handy way of seeing how many lines a tail -f has hit or see how many files find has found. On solaris, you may have to use 'nawk' and your machine needs 'tput' Show Sample Output
This is sample output - yours may be different.
```
13164
```
0

cat /dev/urandom|awk 'BEGIN{"tput cuu1" | getline CursorUp; "tput clear" | getline Clear; printf Clear}{num+=1;printf CursorUp; print num}'

axelabs · 2009-07-13 07:30:51 0
Randomize lines in a file

This appends a random number as a first filed of all lines in SOMEFILE then sorts by the first column and finally cuts of the random numbers.
This is sample output - yours may be different.
4

awk 'BEGIN{srand()}{print rand(),$0}' SOMEFILE | sort -n | cut -d ' ' -f2-

axelabs · 2009-05-29 01:20:50 4
lsof equivalent on solaris

Report fstat(2) and fcntl(2) information for all open files in each process.
This is sample output - yours may be different.
4

/usr/proc/bin/pfiles $PID

axelabs · 2009-03-05 17:26:57 2
Print text string vertically, one character per line.

Show Sample Output
This is sample output - yours may be different.
```
P
r
i
n
t
 
t
e
x
t
 
v
e
r
t
i
c
a
l
l
y
```
8

echo Print text vertically|sed 's/$.$/\1\n/g'

axelabs · 2009-03-04 23:58:02 6
check if commandlinefu.com got a better domain

It would be nice if commandlinefu.com had a better domain name. Will they pick one of the above; We'll see. Show Sample Output
This is sample output - yours may be different.
```
No whois server is known for this kind of object.
No match for "CMDFU.COM".
```
-11

whois cmd.fu;whois cmdfu.com|grep -i cmdfu

axelabs · 2009-02-19 08:57:50 3

What's this?

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