usefull-commands

### change virtual terminal ###
chvt 1 or 7
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### trace process ###
strace ls 2>&1 | tee log ##### redirect stderr and stdout to pipe tee write stdin on console and to the file
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### du size of all dir included hiddens dirs ###
du -sh .[^.]*

### download site ###
wget --recursive --no-clobber --page-requisites --html-extension --convert-links --restrict-file-names=unix,ascii --domains opennet.ru --no-parent http://site.com/doc/ ############ download website
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### cpio archive ###
cpio -idmv < initrd-file
find ./ | cpio -H newc -o > /boot/new-initrd.cpio ###### create cpio archive
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### reqursive substitude ###
find -type f -name \*.h  -exec sed -i -r 's/server\.h"/net\.h"/g' {} \;
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### memory ###
cat /proc/meminfo
cat /proc/sys/vm/swappiness
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### drop all cach ###
echo 1 > /proc/sys/vm/drop_caches && sync && echo 2 > /proc/sys/vm/drop_caches && sync && echo 3 > /proc/sys/vm/drop_caches && sync && free -h
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### io statistic and information about kernel slab ###
iostat slabtop 
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### ifconfig eth0 ${IP_ADDR} broadcast ${BROADCAST} netmask ${NETMASK} up ###
route add default gw ${GATEWAY}
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### find . -name \*.c | xargs grep '^function' ###
find . -type f -exec sh -c 'f={}; #created variables with finded filename
find . -exec grep -H -n 'hello' {} \;  #Hn it is filename and number of string
grep -nHe ^xalloc_die -r .
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### find multiply pattern and action with it ###
find . -name 'afile' -exec cat {} \; -or -name 'bfile' -exec cat {} \;
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### awk ###
echo "username=DefUser2; PRNT=HP:0111020202=yes; HP:0s0dw33333=no; SCAN=HP:0999695444; FLASH=Kingston:5B651F00047B=rw;JetFlash:26HJQV7I57QG86CB=ro;" |  awk -F";"                          '{ for (i=1; i<=NF; i++) { if ($i ~ "username=.*") { print $i } } }' | sed 's/username=//'
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### print used space on mounted volume ###
df
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### get or set hard disks parameters ###
hdparm
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### losetup ###
modprobe -r loop
modprobe loop max_part=64
losetup /dev/loop0 ~/sda_backup

ls -l /dev/loop*
brw-rw--— 1 root disk 7, 0 Apr 4 14:34 /dev/loop0
brw-rw--— 1 root disk 7, 1 Apr 4 14:34 /dev/loop0p1
brw-rw--— 1 root disk 7, 5 Apr 4 14:34 /dev/loop0p5
brw-rw--— 1 root disk 7, 6 Apr 4 14:34 /dev/loop0p6
brw-rw--— 1 root disk 7, 7 Apr 4 14:34 /dev/loop0p7
brw-rw--— 1 root disk 7, 8 Apr 4 14:34 /dev/loop0p8

mount /dev/loop0p1 /mnt/part1/
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### what file is opened on filesystem ###
fuser -mv /mount_point
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### unarchive ###
bzip2 -cd filename.tar.bz2 | tar -xvf -
### concatenate and compress files ###
tar cfJ arch.tar.xz files_to_archive #create xz archive
tar -c * > archeve.tar
bzip2 -z archeve.tar  #result file is archeve.tar.bz2
##################################

#search files which was later date of change than %filename1, ###
### and files which was earlier date of change than %filename2 ###
find /  -not \( -path /root -prune \) -not \( -path /proc -prune \) -not \( -path /sys -prune \) -not \( -path /tmp -prune \) -not \( -path /boot -prune \) -not \( -path /run -prune \) -not \( -path /home -prune \) -not \( -path /media -prune \) -not \( -path /mnt -prune \) -and \( -newer /root/time1 \) -and \( ! -newer /root/time2 \)
find . -iname '*cxoffice*' -a -not -path '*.wine/*'
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### redirect and merge stderr into stdout ###
date > file 2>$1
exec >filename #redirect stdout from all command of the script to "filename"
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### operation with fd ###
n<&- #close input file descriptor n
0<&-, <&- #close stdin
n>&- #close output file descriptor n
1>&-, >&- #close stdout
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#############################################
exec 6<&0 #lonk file descriptor #6 with stdin
exec < data-file
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### read from stdin or file and put it to var ${REPLY} ###
read s1 #read first line from data-file
read s2 #read second line from data-file

### restore stdin and close fd 6 ###
exec 0<&6 6<&- #restore stdin from fd 6 and close fd 6 to free it for system
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### Search  the  short  descriptions  and  manual  page names for the keyword printf as regular #expression. ###
man -k keyword
man -a intro #show all section where the "intro" is exest
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### output the first part of file (head) end of file (tail) ###
head
tail
#############################

### cut - remove sections from each line of files ###
cut
################################

### tr - translate or delete characters ###
tr
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### whatis whereis which ###
whatis    whereis   which
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### nmap - Network exploration tool and security / port scanner ###
nmap -sT server.example.com    # will be scanning port from 0 to 1024
nmap -O -sV server.example.com    # will be scanning ports and detect operation sistem
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### information from obj file ###
objdump
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### run as command in bash their argument ###
xargs
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### list files which lock by PID ###
lsof -p "${PID}"
#################################

### manipulate jobs ###
bg - run jobs in the background
help bg
help fg
help jobs
help disown #detach process from terminal
man bash
info bash
###################################

### detach bg job from terminal ###
dtach
#################################

### immune to SIGHUP signal ###
nohup - run a command immune to hangups, with output to a non-tty
##################################

### write to file and stdout ###
tee # read from standard input and write to standard output and files
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### installed package names ###
aptitude search package_name|sed -n '/^i *./p'|sed 's/^i   //'|sed 's/^i A //'|sed 's/ *- .*//' #cut all from aptitude output without package names
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### prepare file to kernel patch ###
./checkpatch.pl --no-tree -f sourcefile.c #check file for kernel style
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### ls -l as column ###
(printf "PERMISSIONS LINKS OWNER GROUP SIZE MONTH DAY HH:MM PROG-NAME\n" ; ls -l | sed 1d) | column -t #print by columns
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### remove 2 to 4 char from each line ###
colrm 2 4 <filename #remove the second through fourth character from each line of text file "filename"
##################################

### set number of lines ###
nl < .vimrc #inserts numbers of non blanc line
#################################

### prepare file for printing ###
pr filename #prepare for printing file "filename" and put it to stdout
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### read list as array of random digits ###
read -a list < <( od -Ad -w24 -t u2 /dev/urandom ) # list is array of random numbers
##############################

### generate random digit ###
head -c1 /dev/urandom | od -N 1 -i | awk '{ print $2 }' #generate 1 random number
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### print groups in USER is included ###
for i in $(seq 0 $(( "${#GROUPS[@]}" - 1 )) ); do echo ${GROUPS[$i]} ; done #prints numbers of groups in which the user is included
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### changne file format ###
for pic in *"$infmt"; do echo "$pic"; ls "${pic}" | sed -e s/\.$infmt// ; p2=$(ls "$pic" | sed -e s/\.$infmt//); echo "${pic} ${p2}.${outfmt}"; done #change file extension from $infmt to $outfmt
##################################

### patch create and apply ###
diff -Naur standard_moodle my_moodle > difference.patch 
patch -p1 < new_version.patch
#################################

### replacement obsolete netstat and route commands ###
NOTES
       This program is mostly obsolete.  Replacement for netstat is  ss.   Re‐
       placement for netstat -r is ip route.  Replacement for netstat -i is ip
       -s link.  Replacement for netstat -g is ip maddr.

netstat -putna #all tcp connections
netstat -tulpn

ss -l -p -n | egrep 'tcp|udp' #show opened ports
ss -aenp
################################################

### sed print lines between START and END ###
sed -n '/#START#/,/#END#/p' #print all lines between #START# and #END#
##########################################

### to view installed files of certain package
dpkg-query -L <package-name>
dpkg-deb -c /var/cache/apt/archives/package-name.deb
apt-file list <package-name>
#############################

### scp check destination folder is exist and copy ti this folder
scp sourcefile username@ip.address:'`[ -d /dest/dir ] || mkdir -p /dest/dir`/dest/dir/destfile'
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### first syslog record at boot time ###
kernel: [    0.000000] #in vim search: kernel: [    0.000000\]
################################################

### ssh vpn local settings ###
 ip link set dev tun100 up
 ip addr add 192.168.0.2/24 dev tun100
 ip route add "${ssh_server_ip}" via 192.168.1.1 dev wlo1
 ip route del default via 192.168.1.1 dev wlo1
 ip route add default via 192.168.0.1 dev tun100
### ssh vpn remote settings ###
 ip link set dev tun100 up
 ip addr add 192.168.0.1/24 dev tun100
iptables -t nat -A POSTROUTING -s 192.168.0.2/32 -j SNAT --to-source "${uoter_ip}"
echo 1 > /proc/sys/net/ipv4/ip_forward
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### iproute2 change MAC address ###
ip link set dev $IFACE down
ip link set dev $IFACE address XX:XX:XX:XX:XX:XX
ip link set dev $IFACE up

### ssh tunnel from office to internet host ###
#on office host need run sshd on port 22
#on internet host need option PermitTunnel yes
#run next
ssh -N -R 12344:localhost:22 root@internet_host_ip -p12345 &
#om home host to connect to office
ssh user_on_office_host@internet_host_ip -p12344

### cross compile ###
export PATH="/home/ivr/work/buildroot/buildroot-2018.02.4/output_soyuz_new/host/bin:$PATH"
make CC=arm-linux-gcc
### cross compile in kernel stile ###
ARCH=arm CROSS_COMPILE=/usr/bin/arm-linux-gnueabi- make -j10

# ps aux sort by cpu-utilization
ps aux --sort cputime
ps aux --sort -cputime
ps aux --sort -pcpu
ps aux --sort -time