sudo chattr +a Downloads
cd Downloads
rm Ngix.pdf

mv: cannot move ‘Ngix.pdf' to ‘/home/gpx/.trash/Ngix.pdf': Operation not permitted
sudo rm Ngix.pdf
rm: cannot remove ‘Ngix.pdf': Operation not permitted

alias rm='rm -i'
or
alias rm=trash
trash()
{
 mv "$@" trash/
}
or
alias rm='cp $@ ~/backup; rm $@'

#!/bin/sh 
date -d 'now' > /mnt/hd/data/log/rsync.log 
index=1
while :
do
 rsync -azvh --compress-level=0 --progress gpx@ip:/mnt/hd/data/PriceAdj_data/ /mnt/hd/data/PriceAdj_data/ >> /mnt/hd/data/log/rsync.log

 if [ $? -ne 0 ];then
 sleep 5m
 else
 break
 fi

 let "index++"
 if [ $index -eq 5 ];then
 curl -d "operator=alert&phone=number&msg=rsync-dell-data-Failed" "http://ip:port/sendmessage"
 echo "rsync data Failed !" >> /mnt/hd/data/log/rsync.log
 exit 1
 fi
done

date -d 'now' > /mnt/hd/data/log/log_save_dateData.log 
nohup python /mnt/hd/data/code/load_Today_Data.py >> /mnt/hd/data/log/log_save_dateData.log

-v:
--verbose increase verbosity
--info=FLAGS fine-grained informational verbosity
--debug=FLAGS fine-grained debug verbosity
--msgs2stderr special output handling for debugging
-a:
--archive archive mode; equals -rlptgoD (no -H,-A,-X)
--no-OPTION turn off an implied OPTION (e.g. --no-D)
 -z:
--compress compress file data during the transfer
--compress-level=NUM explicitly set compression level
--skip-compress=LIST skip compressing files with suffix in LIST
-h:
--human-readable output numbers in a human-readable format
--progress show progress during transfer
--delete delete extraneous files from dest dirs
scp mode remote_username@remote_hostname(or ip):remote_file_path dest_file_path >> run_log_path
example:
name@host:/mnt/hd/data/code/shell$ scp sql_rsync.sh name@host:/tmp/
name@host's password:
sql_rsync.sh     100% 149 0.2KB/s 00:00
name@host:/mnt/hd/data/code/shell$[b]
接下来给大家总结了10条linux常用命令[/b]