touch command
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With out option-create new file
touch file1
If the file doesn’t exist, an empty file with the same name will be created in the current directory
-m : current tme stamp
touch -m ulupeezcontrol.jar
touch -t (mmddhhmm) ulupeezcontrol.jar
if it is current year no need of year,,,,other wise last 2 digits of the year
if you want to copy a timestamp from a file to another file.
touch –r file1 file2
creating empty file
touch ak.txt
•mtime — updated when the file contents change. This is the "default" file time in most cases.
•ctime — updated when the file or its metadata (owner, permissions) change
•atime — updated when the file is read
ls -l mtime ulupeezconrol.jar
scp Command
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Copy the file "foobar.txt" from remote host "rh1.edu" to remote host "rh2.edu"
scp your_username@rh1.edu:/some/remote/directory/foobar.txt \
your_username@rh2.edu:/some/remote/directory/
GREP Command
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* Find all lines matching a specific keyword on a file
grep ulupeez /etc/passwd
* Option -v, will display all the lines except the match
* To get lines matched the text pattern in a particular file use -c option
grep -c ulupeez /etc/passwd
*get the total number of lines that did not match the specific pattern by passing option -cv
grep -cv ulupeez /etc/passwd
*search a text by ignoring the case
grep -i ulupeez /etc/passwd
*search all subdirectories for a text matching a specific pattern
grep -ri ulupeez /home/users
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*find files containing a specific word in its name
find / -type f -size +100M
*find files that are not modified in the last x number of days
find . -mtime +60
*find files that are modified in the last x number of days
find . –mtime -2
*delete all the archive files with extension *.tar.gz and greater than 100MB
find / -type f -name *.tar.gz -size +100M -exec ls -l {} \;
find / -type f -name *.tar.gz -size +100M -exec rm -f {} \;
*archive all the files that are not modified in the last x number of days
find /home/ulupeez -type f -mtime +60 | xargs tar -cvf /tmp/`date '+%d%m%Y'_archive.tar`
