x permissionfreewatch 'command | othertool | yet-another-tool'stty rows 50 cols 132Reference: How to change the width of remote serial console? [duplicate]
The above solution may cause messed text in Vim. Maybe a better solution is resizable serial console window?.
progress
Toggle display of progress meter.vncserver -fp catalogue:/etc/X11/fontpath.d-fp catalogue:/etc/X11/fontpath.d is required. No idea
of the reason.
It will prompts the password.
ssh -p 10001 user_name@host_ip -L 7000:master:5908master is the host name, 5908 is the port
which the VNC server listens to. 7000 is the port number on
the client side which ssh forwards to 5908.
localhost:7000.ssh user1@server1 date
ssh user1@server1 bash my.sh/etc/ssh/sshd_config to set
PasswordAuthentication no.systemctl restart sshd.servicessh-keygen -E md5 -lf ~/.ssh/id_rsa.pubsftp -oBatchMode=no -b YOUR_COMMAND_FILE_PATH USER@HOSTIf it requires the password, use sshpass to pass the
password.
sshpass -p YOUR_PASSWORD sftp -oBatchMode=no -b YOUR_COMMAND_FILE_PATH USER@HOSTUse -o, which means “or”:
find Documents \( -name "*.py" -o -name "*.html" \)7z -v100m a my_zip.7z my_folder/$ paste f1 f2 | tr -d '\t'
123456789abcdefghij
9876543211111111111
0000000003333333333find . -type fls | grep -v '\.jar$'fbase=PressureContour_SliceCore_REF_G1R2P1It
for f_fullname in ${fbase}[0-9]*; do
fname=${f_fullname%.*}
mv "$f_fullname" $(printf "${fbase}%05d.png" "${fname#${fbase}}")
doneRun the following file as transpose.sh file_name
awk '
{
for (i=1; i<=NF; i++) {
a[NR,i] = $i
}
}
NF>p { p = NF }
END {
for(j=1; j<=p; j++) {
str=a[1,j]
for(i=2; i<=NR; i++){
str=str" "a[i,j];
}
print str
}
}' $1To change all the directories to 755 (drwxr-xr-x):
find /opt/lampp/htdocs -type d -exec chmod 755 {} \;To change all the files to 644 (-rw-r--r--):
find /opt/lampp/htdocs -type f -exec chmod 644 {} \;x permissionTo view the files in a directory, the directory must have a
x permission.
grep -rwnil abc | while read f; do sed -i 's/abc/ref/gI' $f; doneUse unzip -O cp936 file.zip
For example, to find all files in the current directory that have been modified since yesterday (24 hours ago) use:
find . -maxdepth 1 -mtime -1Note that to find files modified before 24 hours ago, you have to use
-mtime +1 instead of -mtime -1.
free❯ free -m
total used free shared buff/cache available
Mem: 191891 22150 1698 4171 168042 164146
Swap: 0 0 0available includes free and a part of
buff/cache.
If free is close to 0, do not worry. If the
following things happen, you must check what is going on.
available memory is close to zeroswap used increases or fluctuatesdmesg | grep oom-killer shows the OutOfMemory-killer at
workyum autoremove [package_name]repoquery --installed -l httpdsystemctl stop [servicename]
systemctl disable [servicename]
rm /etc/systemd/system/[servicename]
rm /etc/systemd/system/[servicename] # and symlinks that might be related
rm /usr/lib/systemd/system/[servicename]
rm /usr/lib/systemd/system/[servicename] # and symlinks that might be related
systemctl daemon-reload
systemctl reset-failedYou can get this information from /proc filesystem, it
stores information about running processes.
cat /proc/<pid>/environ
cd /proc/<pid>/cwd; pwd -P
cat /proc/<pid>/cmdlineAnother method is
lsof -p $PIDThe parameter of lstart of ps does this
job.
ps -eo pid,lstart,cmdps aux | grep nfs_opt | awk '{print $2}' | while read i; do kill -9 $i; doneThe stat of the zombie process is Z.
ps aux | grep 'Z'You have to kill the parent process of the zombie process.
$ pstree -p -s ${zombie_pid}
init(1)---cnid_metad(1311)---cnid_dbd(5145)
$ kill 5145 # Usually kill the 1st oneThe following specfies the width of the column user to
be 16. The key is to use the option o or
-o.
alias ps_mod='ps ax o user:16,pid,pcpu,pmem,vsz,rss,stat,start_time,time,cmd'RED='\033[0;31m'
BLUE='\033[0;34m'
NC='\033[0m' # No Color
echo -e "${RED}The CPU usage(2nd column) and memory usage(3rd column) of the currently login users are as follows,${NC}"
own=$(id -nu)
cpus=$(lscpu | grep "^CPU(s):" | awk '{print $2}')
normal_users=$(cut -d: -f1,3 /etc/passwd | egrep ':[0-9]{4}$' | cut -d: -f1)
# Assume that the length of username is less than 20
proc_users=$(ps ax o user:20 | awk '{print $1}' | sort -u)
proc_normal_users=''
for pu in $proc_users; do
for nu in $normal_users; do
if [[ $pu == $nu ]]; then
proc_normal_users=$proc_normal_users$pu" "
fi
done
done
# for user in $(who | awk '{print $1}' | sort -u)
for user in $proc_normal_users
do
# print other user's CPU usage in parallel but skip own one because
# spawning many processes will increase our CPU usage significantly
if [ "$user" = "$own" ]; then continue; fi
(top -b -n 1 -u "$user" | awk -v user=$user -v CPUS=$cpus 'NR>7 { sum += $9; } END { print user, sum, sum/CPUS; }') &
# don't spawn too many processes in parallel
sleep 0.05
done
wait
# print own CPU usage after all spawned processes completed
top -b -n 1 -u "$own" | awk -v user=$own -v CPUS=$cpus 'NR>7 { sum += $9; } END { print user, sum, sum/CPUS; }'
echo -e "${BLUE}In the 2nd column, 100 means 1 CPU is being used.${NC}"
echo -e "${RED}If someone is using this node, try other nodes please!${NC}"PSR number shows the processor number the process is
assigned to.
Thus use ps -aF or ps -q 7810 -o psr.
sudo nethogs wlan0ffmpeg -i left.mp4 -i right.mp4 -filter_complex hstack output.mp4To stack more than 2 videos, you can simply specify
hstack=inputs=3.
ffmpeg -f concat -safe 0 -i <(for f in ./*.ogv; do echo "file '$PWD/$f'"; done) -c copy output.ogvReference: ffmpeg concat demuxer
convertconvert -delay 25 -loop 0 -quality 100 Pressure*.png Pressure.mp4Note: The video file by convert can be played by video
player but not by Chrome.
ffmpegBy pipe
cat PressureContour_SliceCore_REF_G1R2P1It0*.png | ~/Softwares/ffmpeg/ffmpeg -f image2pipe -framerate 4 -i - -c:v libx264 -pix_fmt yuv420p out.mp4Another method is sequential reading. However, it requires that the
index of the image should be starting from 1. If not, you need to
specify the -start_number 50. But the second index number
should be 51. That is bad design.
The above ffmpeg method produce a video file which is played
perfectly in Chrome but in apps like PotPlayer it shows wrongs frames at
the end of the video file. For example, ffmpeg says this video is
9.23s. PotPlayer says this video is 10s and
shows wrong frames after 9.23s.
Reference: ffmpeg wiki: Create a video slideshow from images
Another problem is that h264 codec requires even dimensions.
ffmpeg -r 24 -i frame_%05d.jpg -vcodec libx264 -y -an video.mp4 -vf "pad=ceil(iw/2)*2:ceil(ih/2)*2"Reference: FFMPEG (libx264) “height not divisible by 2”
Use ffmpeg to convert. Use convert from
imagemagick to reduce size.
ffmpeg -i input.mp4 -pix_fmt rgb24 input_raw.gif
convert -loop 0 -layers Optimize input_raw.gif input.gifTry using -gravity North (this will move your text to
the top of the image) and then adding an offset
(-annotate +0+100) to move down your text:
convert temp.jpg -gravity North -pointsize 30 -annotate +0+100 'Love you mom' temp1.jpgUse pdfcrop
Use pdfinfo
pdfinfo -box input_file.pdfUse Ghostscript. Shell script is as follows,
#!/bin/bash
input_fname=$1
left=$2
bottom=$3
right=$4
top=$5
if [ "$top" == "" ]; then
echo "Usage: ./crop_pdf.sh input_file.pdf left bottom right top"
else
extension="${input_fname##*.}"
filename="${input_fname%.*}"
output_fname="${filename}_crop.pdf"
# Use pdfinfo -box input_file.pdf to get the box info of this pdf.
gs -sDEVICE=pdfwrite -sOutputFile=$output_fname -dBATCH -dNOPAUSE -c "[ /CropBox [ $left $bottom $right $top ] /PAGES pdfmark" -f $input_fname
fiUse pdfjam which is installed by tlmgr in
the TexLive distro. The usage is as
follows,
pdfjam input_location_discontinuous_crop.pdf input_location_merged_crop.pdf --nup 2x1 --outfile input_location.pdf$ scontrol show job 1665191
JobId=1665191 Name=tasktest
...
Shared=OK Contiguous=0 Licenses=(null) Network=(null)
Command=/lustre/work/.../slurm_test/task.submit
WorkDir=/lustre/work/.../slurm_test