This document provides summaries of common Linux commands organized into categories including file commands, process management, file permissions, searching, system info, compression, networking, and shortcuts. The file commands section lists commands for listing, changing directories, viewing contents, creating/deleting files and directories. The process management section covers commands for viewing and killing processes. [/SUMMARY]

2. Linux Commands
File Commands
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ls
ls -al
ls -lt
cd dir
cd
pwd
mkdir dir
cat >file
more file
Directory listing
Formatted listing with hidden files
Sorting the Formatted listing by time modification
Change directory to dir
Change to home directory
Show current working directory
Creating a directory dir
Places the standard input into the file
Output the contents of the file
Output the first 10 lines of the file
Output the last 10 lines of the file
Output the contents of file as it grows,starting with
the last 10 lines
Create or update file
Deleting the file
Deleting the directory
Force to remove the file
Force to remove the directory dir
Copy the contents of file1 to file2
Copy dir1 to dir2;create dir2 if not present
Rename or move file1 to file2,if file2 is an existing
directory
Create symbolic link link to file
10. head file
11. tail file
12. tail -f file
13. touch file
14. rm file
15. rm -r dir
16. rm -f file
17. rm -rf dir
18. cp file1 file2
19. cp -r dir1 dir2
20. mv file1 file2
21. ln -s file link
Process management
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ps
top
To display the currently working processes
Display all running process

3. SHIVA BHARDWAJ
SHIVA BHARDWAJ
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kill pid
killall proc
pkill pattern
bg
fg
fg n
Kill the process with given pid
Kill all the process named proc
Will kill all processes matching the pattern
List stopped or background jobs,resume a stopped
job in the background
Brings the most recent job to foreground
Brings job n to the foreground
File permission
1. chmod octal file Change the permission of file to octal,which can
be found separately for user,group,world by
adding,
•4-read(r)
•2-write(w)
•1-execute(x)
Searching
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grep pattern file
grep -r pattern dir
command | grep
pattern
locate file
find . -name filename
Search for pattern in file
Search recursively for pattern in dir
Search pattern in the output of a command
Find all instances of file
Searches in the current directory (represented by
a period) and below it, for files and directories with
names starting with filename
Searches for all the named processes , that
matches with the pattern and, by default, returns
their ID
6. pgrep pattern
System Info
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date
cal
uptime
w
whoami
Show the current date and time
Show this month's calender
Show current uptime
Display who is on line
Who you are logged in as

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finger user
uname -a
cat /proc/cpuinfo
cat proc/meminfo
Display information about user
Show kernel information
Cpu information
Memory information
Show the manual for command
Show the disk usage
Show directory space usage
Show memory and swap usage
Show possible locations of app
Show which applications will be run by default
10. man command
11. df
12. du
13. free
14. whereis app
15. which app
Compression
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tar cf file.tar file
tar xf file.tar
tar czf file.tar.gz files
tar xzf file.tar.gz
tar cjf file.tar.bz2
tar xjf file.tar.bz2
gzip file
gzip -d file.gz
Create tar named file.tar containing file
Extract the files from file.tar
Create a tar with Gzip compression
Extract a tar using Gzip
Create tar with Bzip2 compression
Extract a tar using Bzip2
Compresses file and renames it to file.gz
Decompresses file.gz back to file
Network
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ping host
whois domain
dig domain
dig -x host
wget file
wget -c file
Ping host and output results
Get whois information for domains
Get DNS information for domain
Reverse lookup host
Download file
Continue a stopped download

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Shortcuts
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ctrl+c
ctrl+z
ctrl+d
ctrl+w
ctrl+u
ctrl+r
!!
exit
Halts the current command
Stops the current command, resume with fg in the
foreground or bg in the background
Logout the current session, similar to exit
Erases one word in the current line
Erases the whole line
Type to bring up a recent command
Repeats the last command
Logout the current session