Difference between revisions of "Linux command line"
From ScientificComputing
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| − | Bash is a powerful scripting language, which can directly been used in a Linux terminal. It can simplify the many tasks when you are working on a HPC cluster. Therefore we recommend to study at least some of the basic Linux and bash commands, before you start using the clusters. Below we give examples for bash and the most widely used Linux commands. | + | Bash is a powerful scripting language, which can directly been used in a Linux terminal and is often combined with Linux commands. It can simplify the many tasks when you are working on a HPC cluster. Therefore we recommend to study at least some of the basic Linux and bash commands, before you start using the clusters. Below we give examples for bash and the most widely used Linux commands. |
| + | |||
| + | ==Bash== | ||
* specify a variable and print its value to the standard output | * specify a variable and print its value to the standard output | ||
| Line 33: | Line 35: | ||
<br> | <br> | ||
| − | + | == Linux commands == | |
'''''ls''''' | '''''ls''''' | ||
| + | |||
* Display list of files and folders sorted by time in reversed order (newest files at the bottom), including hidden files. | * Display list of files and folders sorted by time in reversed order (newest files at the bottom), including hidden files. | ||
| − | [leonhard@euler01 test]$ ls -ltra | + | [leonhard@euler01 test]$ '''ls -ltra''' |
total 1619 | total 1619 | ||
-rw-r--r-- 1 leonhard T0000 166 Jun 13 17:12 file2 | -rw-r--r-- 1 leonhard T0000 166 Jun 13 17:12 file2 | ||
| Line 48: | Line 51: | ||
drwxr-xr-x 2 leonhard T0000 7 Jun 13 17:15 . | drwxr-xr-x 2 leonhard T0000 7 Jun 13 17:15 . | ||
* Display list of files sorted by filesize in reversed order (largest files at the bottom), including hidden files. | * Display list of files sorted by filesize in reversed order (largest files at the bottom), including hidden files. | ||
| − | [leonhard@euler01 test]$ ls -lSra | + | [leonhard@euler01 test]$ '''ls -lSra''' |
total 1619 | total 1619 | ||
drwxr-xr-x 2 leonhard T0000 7 Jun 13 17:15 . | drwxr-xr-x 2 leonhard T0000 7 Jun 13 17:15 . | ||
| Line 59: | Line 62: | ||
'''''cd''''' | '''''cd''''' | ||
| + | |||
* Change to your home directory. | * Change to your home directory. | ||
cd ~ | cd ~ | ||
| Line 67: | Line 71: | ||
'''''pwd''''' | '''''pwd''''' | ||
| + | |||
* Print working directory. | * Print working directory. | ||
| − | [leonhard@euler01 test]$ pwd | + | [leonhard@euler01 test]$ '''pwd''' |
| − | /cluster/home/ | + | /cluster/home/leonhard/test |
'''''echo''''' | '''''echo''''' | ||
| + | |||
* Print a string to the standard output. | * Print a string to the standard output. | ||
| − | [leonhard@euler01 test]$ echo this goes to the standard output | + | [leonhard@euler01 test]$ '''echo "this goes to the standard output"''' |
this goes to the standard output | this goes to the standard output | ||
'''''less''''', '''''cat''''', '''''more''''' | '''''less''''', '''''cat''''', '''''more''''' | ||
| + | |||
* Display the content of a file. | * Display the content of a file. | ||
less ''file'' | less ''file'' | ||
| Line 85: | Line 92: | ||
'''''cp''''' | '''''cp''''' | ||
| + | |||
* Copy a file. | * Copy a file. | ||
| − | [leonhard@euler01 test]$ ls -l | + | [leonhard@euler01 test]$ '''ls -l''' |
total 1540 | total 1540 | ||
-rw-r--r-- 1 leonhard T0000 1488156 Jun 13 17:14 file1 | -rw-r--r-- 1 leonhard T0000 1488156 Jun 13 17:14 file1 | ||
| − | [leonhard@euler01 test]$ cp file1 file2 | + | [leonhard@euler01 test]$ '''cp file1 file2''' |
| − | [leonhard@euler01 test]$ ls -l | + | [leonhard@euler01 test]$ '''ls -l''' |
total 1540 | total 1540 | ||
-rw-r--r-- 1 leonhard T0000 1488156 Jun 13 17:14 file1 | -rw-r--r-- 1 leonhard T0000 1488156 Jun 13 17:14 file1 | ||
-rw-r--r-- 1 leonhard T0000 1488156 Jun 13 17:26 file2 | -rw-r--r-- 1 leonhard T0000 1488156 Jun 13 17:26 file2 | ||
* Copy a directory. | * Copy a directory. | ||
| − | [leonhard@euler01 test]$ ls -l | + | [leonhard@euler01 test]$ '''ls -l''' |
total 1 | total 1 | ||
drwxr-xr-x 2 leonhard T0000 2 Jun 13 17:26 testdir1 | drwxr-xr-x 2 leonhard T0000 2 Jun 13 17:26 testdir1 | ||
| − | [leonhard@euler01 test]$ cp -r testdir1 testdir2 | + | [leonhard@euler01 test]$ '''cp -r testdir1 testdir2''' |
| − | [leonhard@euler01 test]$ ls -l | + | [leonhard@euler01 test]$ '''ls -l''' |
total 2 | total 2 | ||
drwxr-xr-x 2 leonhard T0000 2 Jun 13 17:26 testdir1 | drwxr-xr-x 2 leonhard T0000 2 Jun 13 17:26 testdir1 | ||
| Line 106: | Line 114: | ||
'''''mv''''' | '''''mv''''' | ||
| + | |||
* Rename a file. | * Rename a file. | ||
| − | [leonhard@euler01 test]$ ls -l | + | [leonhard@euler01 test]$ '''ls -l''' |
total 1 | total 1 | ||
-rw-r--r-- 1 leonhard T0000 10 Jun 13 17:28 file1 | -rw-r--r-- 1 leonhard T0000 10 Jun 13 17:28 file1 | ||
| − | [leonhard@euler01 test]$ mv file1 file2 | + | [leonhard@euler01 test]$ '''mv file1 file2''' |
| − | [leonhard@euler01 test]$ ls -l | + | [leonhard@euler01 test]$ '''ls -l''' |
total 1 | total 1 | ||
-rw-r--r-- 1 leonhard T0000 10 Jun 13 17:28 file2 | -rw-r--r-- 1 leonhard T0000 10 Jun 13 17:28 file2 | ||
'''''rm''''' | '''''rm''''' | ||
| + | |||
* Delete a file. | * Delete a file. | ||
[leonhard@euler01 test]$ ls -l | [leonhard@euler01 test]$ ls -l | ||
total 1 | total 1 | ||
-rw-r--r-- 1 leonhard T0000 10 Jun 13 17:28 file2 | -rw-r--r-- 1 leonhard T0000 10 Jun 13 17:28 file2 | ||
| − | [leonhard@euler01 test]$ rm file2 | + | [leonhard@euler01 test]$ '''rm file2''' |
| − | [leonhard@euler01 test]$ ls -l | + | [leonhard@euler01 test]$ '''ls -l''' |
total 0 | total 0 | ||
* Delete a directory (no matter if it contains files or not). | * Delete a directory (no matter if it contains files or not). | ||
| − | [leonhard@euler01 test]$ ls -l | + | [leonhard@euler01 test]$ '''ls -l''' |
total 1 | total 1 | ||
| − | drwxr-xr-x 2 | + | drwxr-xr-x 2 leonhard T0000 2 Jun 13 17:30 testdir1 |
| − | [leonhard@euler01 test]$ rm -r testdir1 | + | [leonhard@euler01 test]$ '''rm -r testdir1''' |
| − | [leonhard@euler01 test]$ ls -l | + | [leonhard@euler01 test]$ '''ls -l''' |
total 0 | total 0 | ||
'''''mkdir''''' | '''''mkdir''''' | ||
| + | |||
* Create a directory. | * Create a directory. | ||
| − | [leonhard@euler01 test]$ ls -l | + | [leonhard@euler01 test]$ '''ls -l''' |
total 0 | total 0 | ||
| − | [leonhard@euler01 test]$ mkdir testdir1 | + | [leonhard@euler01 test]$ '''mkdir testdir1''' |
| − | [leonhard@euler01 test]$ ls -l | + | [leonhard@euler01 test]$ '''ls -l''' |
total 1 | total 1 | ||
drwxr-xr-x 2 leonhard T0000 2 Jun 13 17:31 testdir1 | drwxr-xr-x 2 leonhard T0000 2 Jun 13 17:31 testdir1 | ||
'''''rmdir''''' | '''''rmdir''''' | ||
| + | |||
* Delete a directory (deletes only empty directories). | * Delete a directory (deletes only empty directories). | ||
| − | [leonhard@euler01 test]$ ls -l | + | [leonhard@euler01 test]$ '''ls -l''' |
total 1 | total 1 | ||
drwxr-xr-x 2 sfux sdid 2 Jun 13 17:31 testdir1 | drwxr-xr-x 2 sfux sdid 2 Jun 13 17:31 testdir1 | ||
| − | [leonhard@euler01 test]$ rmdir testdir1 | + | [leonhard@euler01 test]$ '''rmdir testdir1''' |
| − | [leonhard@euler01 test]$ ls -l | + | [leonhard@euler01 test]$ '''ls -l''' |
total 0 | total 0 | ||
'''''man''''' | '''''man''''' | ||
| + | |||
* Display the manual of a Linux command (output is too large to display it here, but just try it out). | * Display the manual of a Linux command (output is too large to display it here, but just try it out). | ||
man ls | man ls | ||
| Line 155: | Line 168: | ||
'''''exit''''' | '''''exit''''' | ||
| − | * | + | |
| − | [leonhard@euler01 ~]$ exit | + | * Terminate and exit the current shell. |
| + | [leonhard@euler01 ~]$ '''exit''' | ||
logout | logout | ||
| − | Connection to | + | Connection to euler.ethz.ch closed. |
| − | + | leonhard@calculus:~$ | |
'''''vi''''', '''''nano''''' | '''''vi''''', '''''nano''''' | ||
| + | |||
* Try out the text editors by displaying a file. | * Try out the text editors by displaying a file. | ||
vi ''file'' | vi ''file'' | ||
| Line 168: | Line 183: | ||
'''''grep''''' | '''''grep''''' | ||
| + | |||
* Search for a string within another string or a file. | * Search for a string within another string or a file. | ||
| − | [leonhard@euler01 test]$ ls -l | + | [leonhard@euler01 test]$ '''ls -l''' |
total 2 | total 2 | ||
-rw-r--r-- 1 leonhard T0000 0 Jun 13 17:44 file11 | -rw-r--r-- 1 leonhard T0000 0 Jun 13 17:44 file11 | ||
| Line 175: | Line 191: | ||
-rw-r--r-- 1 leonhard T0000 0 Jun 13 17:43 testfile1 | -rw-r--r-- 1 leonhard T0000 0 Jun 13 17:43 testfile1 | ||
-rw-r--r-- 1 leonhard T0000 0 Jun 13 17:43 testfile2 | -rw-r--r-- 1 leonhard T0000 0 Jun 13 17:43 testfile2 | ||
| − | [leonhard@euler01 test]$ ls -l | grep test | + | [leonhard@euler01 test]$ '''ls -l | grep test''' |
-rw-r--r-- 1 leonhard T0000 0 Jun 13 17:43 testfile1 | -rw-r--r-- 1 leonhard T0000 0 Jun 13 17:43 testfile1 | ||
-rw-r--r-- 1 leonhard T0000 0 Jun 13 17:43 testfile2 | -rw-r--r-- 1 leonhard T0000 0 Jun 13 17:43 testfile2 | ||
'''''sort''''' | '''''sort''''' | ||
| + | |||
* Sort a file line by line | * Sort a file line by line | ||
| − | [leonhard@euler01 test]$ more file1 | + | [leonhard@euler01 test]$ '''more file1''' |
c line c | c line c | ||
b line b | b line b | ||
d line d | d line d | ||
a line a | a line a | ||
| − | [leonhard@euler01 test]$ sort file1 | + | [leonhard@euler01 test]$ '''sort file1''' |
a line a | a line a | ||
b line b | b line b | ||
| Line 193: | Line 210: | ||
'''''sed''''' | '''''sed''''' | ||
| + | |||
* Powerful tool for string manipulation (even whole files) which has many more functions. Exchange part of a string by another one (see also bash examples) | * Powerful tool for string manipulation (even whole files) which has many more functions. Exchange part of a string by another one (see also bash examples) | ||
| − | [leonhard@euler01 test]$ echo what a beautyful day | sed s/day/night/ | + | [leonhard@euler01 test]$ '''echo what a beautyful day | sed s/day/night/''' |
what a beautyful night | what a beautyful night | ||
[leonhard@euler01 test]$ | [leonhard@euler01 test]$ | ||
'''''awk''''' | '''''awk''''' | ||
| + | |||
* Awk is really a programming language. It can process text, perform arithmetic operations, etc. It is usually used in combination with another command to process/extract information. For example, to find out how many jobs are pending/running on the cluster: | * Awk is really a programming language. It can process text, perform arithmetic operations, etc. It is usually used in combination with another command to process/extract information. For example, to find out how many jobs are pending/running on the cluster: | ||
| − | [leonhard@euler01 ~]$ bqueues | + | |
| + | [leonhard@euler01 ~]$ '''bqueues''' | ||
QUEUE_NAME PRIO STATUS MAX JL/U JL/P JL/H NJOBS PEND RUN SUSP | QUEUE_NAME PRIO STATUS MAX JL/U JL/P JL/H NJOBS PEND RUN SUSP | ||
| − | + | clc 94 Open:Active 256 - - - 0 0 0 0 | |
| − | + | bigmem.4h 88 Open:Active - - - - 264 240 24 0 | |
| − | + | bigmem.24h 86 Open:Active - - - - 3031 2550 481 0 | |
| − | + | bigmem.120h 84 Open:Active - 960 - - 834 416 418 0 | |
| − | + | normal.4h 68 Open:Active - - - - 7520 5431 2089 0 | |
| − | + | normal.24h 66 Open:Active - - - - 72830 66192 6638 0 | |
| − | + | normal.120h 64 Open:Active - - - - 13666 5251 8415 0 | |
| − | + | normal.30d 62 Open:Active - - - - 58 58 0 0 | |
| − | + | virtual.40d 58 Open:Active - - - - 0 0 0 0 | |
| − | purgatory 1 Open:Inact - - - - | + | light.5d 10 Open:Active - - - - 1 0 1 0 |
| − | [leonhard@euler01 ~]$ bqueues | awk 'BEGIN{p=0;r=0} NR>1{p+=$9;r+=$10} END{printf "Pending:%8i\nRunning:%8i\n",p,r}' | + | purgatory 1 Open:Inact - - - - 4 4 0 0 |
| − | Pending: | + | |
| − | Running: | + | [leonhard@euler01 ~]$ '''bqueues | awk 'BEGIN{p=0;r=0} NR>1{p+=$9;r+=$10} END{printf "Pending:%8i\nRunning:%8i\n",p,r}'''' |
| + | Pending: 80142 | ||
| + | Running: 18069 | ||
'''''find''''' | '''''find''''' | ||
| + | |||
Search a string (substitute 'searchstring' by the string you are searching for) in all files contained in the current directory and all its subdirectories. | Search a string (substitute 'searchstring' by the string you are searching for) in all files contained in the current directory and all its subdirectories. | ||
find . -type f -exec grep -q 'searchstring' {} \; -a -exec ls -l {} \; | find . -type f -exec grep -q 'searchstring' {} \; -a -exec ls -l {} \; | ||
'''''du''''' | '''''du''''' | ||
| + | |||
*Go to a directory and display the total size of it and then the sizes of all subdirectories. | *Go to a directory and display the total size of it and then the sizes of all subdirectories. | ||
| − | [leonhard@euler01 mathematica]$ du -hs | + | [leonhard@euler01 mathematica]$ '''du -hs''' |
8.6M . | 8.6M . | ||
| − | [leonhard@euler01 mathematica]$ du -h | + | [leonhard@euler01 mathematica]$ '''du -h''' |
17K ./parallel | 17K ./parallel | ||
5.0K ./batch_mode | 5.0K ./batch_mode | ||
| Line 234: | Line 258: | ||
'''''tar''''' | '''''tar''''' | ||
*Create a tar archive including several files. | *Create a tar archive including several files. | ||
| − | [leonhard@euler01 test]$ ls | + | [leonhard@euler01 test]$ '''ls''' |
PtCO.t21 t21.C t21.O t21.Pt | PtCO.t21 t21.C t21.O t21.Pt | ||
| − | [leonhard@euler01 test]$ tar -cf test.tar * | + | [leonhard@euler01 test]$ '''tar -cf test.tar *''' |
| − | [leonhard@euler01 test]$ ls -ltr | + | [leonhard@euler01 test]$ '''ls -ltr''' |
total 5903 | total 5903 | ||
-rw------- 1 leonhard T0000 675840 May 23 15:27 t21.Pt | -rw------- 1 leonhard T0000 675840 May 23 15:27 t21.Pt | ||
| Line 246: | Line 270: | ||
'''''gzip''''' | '''''gzip''''' | ||
| + | |||
*Compress a file or an archive (tar and gzip are often used together) using gzip. | *Compress a file or an archive (tar and gzip are often used together) using gzip. | ||
| − | [leonhard@euler01 test]$ ls -ltr | + | [leonhard@euler01 test]$ '''ls -ltr''' |
total 2821 | total 2821 | ||
-rw-r--r-- 1 leonhard T0000 2775040 Jun 15 15:48 test.tar | -rw-r--r-- 1 leonhard T0000 2775040 Jun 15 15:48 test.tar | ||
| − | [leonhard@euler01 test]$ gzip test.tar | + | [leonhard@euler01 test]$ '''gzip test.tar''' |
| − | [ | + | [leonhard@euler01 test]$ '''ls -ltr''' |
total 1 | total 1 | ||
-rw-r--r-- 1 leonhard T0000 730947 Jun 15 15:48 test.tar.gz | -rw-r--r-- 1 leonhard T0000 730947 Jun 15 15:48 test.tar.gz | ||
| − | [leonhard@euler01 test]$ gunzip test.tar.gz | + | [leonhard@euler01 test]$ '''gunzip test.tar.gz''' |
| − | [leonhard@euler01 test]$ ls -ltr | + | [leonhard@euler01 test]$ '''ls -ltr''' |
total 1 | total 1 | ||
-rw-r--r-- 1 leonhard T0000 2775040 Jun 15 15:48 test.tar | -rw-r--r-- 1 leonhard T0000 2775040 Jun 15 15:48 test.tar | ||
'''''bzip2''''' | '''''bzip2''''' | ||
| + | |||
*Compress a file or an archive using bzip2 | *Compress a file or an archive using bzip2 | ||
| − | [leonhard@euler01 test]$ ls -ltr | + | [leonhard@euler01 test]$ '''ls -ltr''' |
total 2820 | total 2820 | ||
-rw-r--r-- 1 leonhard T0000 2775040 Jun 15 15:48 test.tar | -rw-r--r-- 1 leonhard T0000 2775040 Jun 15 15:48 test.tar | ||
| − | [leonhard@euler01 test]$ bzip2 test.tar | + | [leonhard@euler01 test]$ '''bzip2 test.tar''' |
| − | [leonhard@euler01 test]$ ls -ltr | + | [leonhard@euler01 test]$ '''ls -ltr''' |
total 1 | total 1 | ||
-rw-r--r-- 1 leonhard T0000 638158 Jun 15 15:48 test.tar.bz2 | -rw-r--r-- 1 leonhard T0000 638158 Jun 15 15:48 test.tar.bz2 | ||
| − | [leonhard@euler01 test]$ bunzip2 test.tar.bz2 | + | [leonhard@euler01 test]$ '''bunzip2 test.tar.bz2''' |
| − | [leonhard@euler01 test]$ ls -ltr | + | [leonhard@euler01 test]$ '''ls -ltr''' |
total 1 | total 1 | ||
-rw-r--r-- 1 leonhard T0000 2775040 Jun 15 15:48 test.tar'''' | -rw-r--r-- 1 leonhard T0000 2775040 Jun 15 15:48 test.tar'''' | ||
Revision as of 08:45, 17 August 2016
Bash is a powerful scripting language, which can directly been used in a Linux terminal and is often combined with Linux commands. It can simplify the many tasks when you are working on a HPC cluster. Therefore we recommend to study at least some of the basic Linux and bash commands, before you start using the clusters. Below we give examples for bash and the most widely used Linux commands.
Bash
- specify a variable and print its value to the standard output
[leonhard@euler01 ~]$ VAR_A="some string variable" [leonhard@euler01 ~]$ echo $VAR_A some string variable
- Print numbers 1-5 to standard output with a for loop
[leonhard@euler01 ~]$ for i in {1..5}; do echo $i; done
1
2
3
4
5
- Print all numbers with two digits to standard output without using a for loop
[leonhard@euler01 ~]$ echo {0..9}{0..9}
00 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33
34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67
68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99
- Print 5 random number to standard output and index them
[leonhard@euler01 test]$ for i in {1..5}; do echo "$i-th random number $RANDOM"; done
1-th random number 25702
2-th random number 21605
3-th random number 6648
4-th random number 13259
5-th random number 8814
- Do manipulations on a string (for instance exchange "home" by "work" in "/cluster/home/leonhard")
[leonhard@euler01 ~]$ STRING1="/cluster/home/leonhard"
[leonhard@euler01 ~]$ echo ${STRING1/home/work}
/cluster/work/leonhard
Linux commands
ls
- Display list of files and folders sorted by time in reversed order (newest files at the bottom), including hidden files.
[leonhard@euler01 test]$ ls -ltra total 1619 -rw-r--r-- 1 leonhard T0000 166 Jun 13 17:12 file2 -rw-r--r-- 1 leonhard T0000 26096 Jun 13 17:13 .file3 -rw-r--r-- 1 leonhard T0000 44642 Jun 13 17:14 file4 -rw-r--r-- 1 leonhard T0000 1488156 Jun 13 17:14 file1 -rw-r--r-- 1 leonhard T0000 73 Jun 13 17:15 file5 drwx------ 71 leonhard T0000 117 Jun 13 17:15 .. drwxr-xr-x 2 leonhard T0000 7 Jun 13 17:15 .
- Display list of files sorted by filesize in reversed order (largest files at the bottom), including hidden files.
[leonhard@euler01 test]$ ls -lSra total 1619 drwxr-xr-x 2 leonhard T0000 7 Jun 13 17:15 . -rw-r--r-- 1 leonhard T0000 73 Jun 13 17:15 file5 drwx------ 71 leonhard T0000 117 Jun 13 17:15 .. -rw-r--r-- 1 leonhard T0000 166 Jun 13 17:12 file2 -rw-r--r-- 1 leonhard T0000 26096 Jun 13 17:13 .file3 -rw-r--r-- 1 leonhard T0000 44642 Jun 13 17:14 file4 -rw-r--r-- 1 leonhard T0000 1488156 Jun 13 17:14 file1
cd
- Change to your home directory.
cd ~
- Go one level up in the directory hierarchy.
cd ..
- Change to a directory with path: /path/to/directory.
cd /path/to/directory
pwd
- Print working directory.
[leonhard@euler01 test]$ pwd /cluster/home/leonhard/test
echo
- Print a string to the standard output.
[leonhard@euler01 test]$ echo "this goes to the standard output" this goes to the standard output
less, cat, more
- Display the content of a file.
less file
or
cat file
or
more file
cp
- Copy a file.
[leonhard@euler01 test]$ ls -l total 1540 -rw-r--r-- 1 leonhard T0000 1488156 Jun 13 17:14 file1 [leonhard@euler01 test]$ cp file1 file2 [leonhard@euler01 test]$ ls -l total 1540 -rw-r--r-- 1 leonhard T0000 1488156 Jun 13 17:14 file1 -rw-r--r-- 1 leonhard T0000 1488156 Jun 13 17:26 file2
- Copy a directory.
[leonhard@euler01 test]$ ls -l total 1 drwxr-xr-x 2 leonhard T0000 2 Jun 13 17:26 testdir1 [leonhard@euler01 test]$ cp -r testdir1 testdir2 [leonhard@euler01 test]$ ls -l total 2 drwxr-xr-x 2 leonhard T0000 2 Jun 13 17:26 testdir1 drwxr-xr-x 2 leonhard T0000 2 Jun 13 17:27 testdir2 [leonhard@euler01 test]$
mv
- Rename a file.
[leonhard@euler01 test]$ ls -l total 1 -rw-r--r-- 1 leonhard T0000 10 Jun 13 17:28 file1 [leonhard@euler01 test]$ mv file1 file2 [leonhard@euler01 test]$ ls -l total 1 -rw-r--r-- 1 leonhard T0000 10 Jun 13 17:28 file2
rm
- Delete a file.
[leonhard@euler01 test]$ ls -l total 1 -rw-r--r-- 1 leonhard T0000 10 Jun 13 17:28 file2 [leonhard@euler01 test]$ rm file2 [leonhard@euler01 test]$ ls -l total 0
- Delete a directory (no matter if it contains files or not).
[leonhard@euler01 test]$ ls -l total 1 drwxr-xr-x 2 leonhard T0000 2 Jun 13 17:30 testdir1 [leonhard@euler01 test]$ rm -r testdir1 [leonhard@euler01 test]$ ls -l total 0
mkdir
- Create a directory.
[leonhard@euler01 test]$ ls -l total 0 [leonhard@euler01 test]$ mkdir testdir1 [leonhard@euler01 test]$ ls -l total 1 drwxr-xr-x 2 leonhard T0000 2 Jun 13 17:31 testdir1
rmdir
- Delete a directory (deletes only empty directories).
[leonhard@euler01 test]$ ls -l total 1 drwxr-xr-x 2 sfux sdid 2 Jun 13 17:31 testdir1 [leonhard@euler01 test]$ rmdir testdir1 [leonhard@euler01 test]$ ls -l total 0
man
- Display the manual of a Linux command (output is too large to display it here, but just try it out).
man ls man screen
exit
- Terminate and exit the current shell.
[leonhard@euler01 ~]$ exit logout Connection to euler.ethz.ch closed. leonhard@calculus:~$
vi, nano
- Try out the text editors by displaying a file.
vi file
or
nano file
grep
- Search for a string within another string or a file.
[leonhard@euler01 test]$ ls -l total 2 -rw-r--r-- 1 leonhard T0000 0 Jun 13 17:44 file11 -rw-r--r-- 1 leonhard T0000 0 Jun 13 17:44 file20 -rw-r--r-- 1 leonhard T0000 0 Jun 13 17:43 testfile1 -rw-r--r-- 1 leonhard T0000 0 Jun 13 17:43 testfile2 [leonhard@euler01 test]$ ls -l | grep test -rw-r--r-- 1 leonhard T0000 0 Jun 13 17:43 testfile1 -rw-r--r-- 1 leonhard T0000 0 Jun 13 17:43 testfile2
sort
- Sort a file line by line
[leonhard@euler01 test]$ more file1 c line c b line b d line d a line a [leonhard@euler01 test]$ sort file1 a line a b line b c line c d line d
sed
- Powerful tool for string manipulation (even whole files) which has many more functions. Exchange part of a string by another one (see also bash examples)
[leonhard@euler01 test]$ echo what a beautyful day | sed s/day/night/ what a beautyful night [leonhard@euler01 test]$
awk
- Awk is really a programming language. It can process text, perform arithmetic operations, etc. It is usually used in combination with another command to process/extract information. For example, to find out how many jobs are pending/running on the cluster:
[leonhard@euler01 ~]$ bqueues QUEUE_NAME PRIO STATUS MAX JL/U JL/P JL/H NJOBS PEND RUN SUSP clc 94 Open:Active 256 - - - 0 0 0 0 bigmem.4h 88 Open:Active - - - - 264 240 24 0 bigmem.24h 86 Open:Active - - - - 3031 2550 481 0 bigmem.120h 84 Open:Active - 960 - - 834 416 418 0 normal.4h 68 Open:Active - - - - 7520 5431 2089 0 normal.24h 66 Open:Active - - - - 72830 66192 6638 0 normal.120h 64 Open:Active - - - - 13666 5251 8415 0 normal.30d 62 Open:Active - - - - 58 58 0 0 virtual.40d 58 Open:Active - - - - 0 0 0 0 light.5d 10 Open:Active - - - - 1 0 1 0 purgatory 1 Open:Inact - - - - 4 4 0 0
[leonhard@euler01 ~]$ bqueues | awk 'BEGIN{p=0;r=0} NR>1{p+=$9;r+=$10} END{printf "Pending:%8i\nRunning:%8i\n",p,r}'
Pending: 80142
Running: 18069
find
Search a string (substitute 'searchstring' by the string you are searching for) in all files contained in the current directory and all its subdirectories.
find . -type f -exec grep -q 'searchstring' {} \; -a -exec ls -l {} \;
du
- Go to a directory and display the total size of it and then the sizes of all subdirectories.
[leonhard@euler01 mathematica]$ du -hs 8.6M . [leonhard@euler01 mathematica]$ du -h 17K ./parallel 5.0K ./batch_mode 24K ./plot_graphics 1.3M ./ptest 7.3M ./ptest2 8.6M .
tar
- Create a tar archive including several files.
[leonhard@euler01 test]$ ls PtCO.t21 t21.C t21.O t21.Pt [leonhard@euler01 test]$ tar -cf test.tar * [leonhard@euler01 test]$ ls -ltr total 5903 -rw------- 1 leonhard T0000 675840 May 23 15:27 t21.Pt -rw------- 1 leonhard T0000 442368 May 23 15:27 t21.O -rw------- 1 leonhard T0000 442368 May 23 15:27 t21.C -rw------- 1 leonhard T0000 1204224 May 23 15:27 PtCO.t21 -rw-r--r-- 1 leonhard T0000 2775040 Jun 15 15:48 test.tar
gzip
- Compress a file or an archive (tar and gzip are often used together) using gzip.
[leonhard@euler01 test]$ ls -ltr total 2821 -rw-r--r-- 1 leonhard T0000 2775040 Jun 15 15:48 test.tar [leonhard@euler01 test]$ gzip test.tar [leonhard@euler01 test]$ ls -ltr total 1 -rw-r--r-- 1 leonhard T0000 730947 Jun 15 15:48 test.tar.gz [leonhard@euler01 test]$ gunzip test.tar.gz [leonhard@euler01 test]$ ls -ltr total 1 -rw-r--r-- 1 leonhard T0000 2775040 Jun 15 15:48 test.tar
bzip2
- Compress a file or an archive using bzip2
[leonhard@euler01 test]$ ls -ltr total 2820 -rw-r--r-- 1 leonhard T0000 2775040 Jun 15 15:48 test.tar [leonhard@euler01 test]$ bzip2 test.tar [leonhard@euler01 test]$ ls -ltr total 1 -rw-r--r-- 1 leonhard T0000 638158 Jun 15 15:48 test.tar.bz2 [leonhard@euler01 test]$ bunzip2 test.tar.bz2 [leonhard@euler01 test]$ ls -ltr total 1 -rw-r--r-- 1 leonhard T0000 2775040 Jun 15 15:48 test.tar'
