There are a selection of the way to view information on Linux, as a result of, in any case, information on Linux are multifaceted. They’ve names, they’ve content material, they’ve entry permissions, and so they have dates and occasions related to their “start” (after they had been initially added to the file system) in addition to after they had been final modified and final accessed. This put up covers the instructions that will let you view all these particulars.
Itemizing information
The simplest and most evident option to checklist information is with the ls command. By default, ls will checklist information within the present listing in title order, however you’ll be able to reverse that by including the -r choice.
$ ls | head -3 4letters 4_vowel_words 4Vwords $ ls -r | head -3 zoom-mtg zodiac zipfiles.bat
You’ll be able to checklist information in a tree-like vogue by utilizing the tree command. It can show the listing construction in a means that clearly signifies the listing ranges.
$ tree . │ ├── xtra │ │ ├── date │ │ ├── doit │ │ ├── dt │ │ ├── ex │ │ ├── loop
Extra data on itemizing and viewing information can be found at these pages:
Viewing entry permissions
The ls command with the -l choice shows permissions within the “rwx” vogue. By including “a” to the choices, it is going to embrace information and directories that begin with a “,” (in any other case omitted).
$ ls -l | head -5 complete 120528 -rw-r-----. 1 shs shs 66040 Jul 5 2022 4letters -rw-r-----. 1 shs shs 174 Jul 8 2022 4_vowel_words -rw-r-----. 1 shs shs 174 Jul 8 2022 4Vwords -rw-r-----+ 1 shs shs 131310 Sep 19 2022 5letters $ ls -al | head -5 complete 133480 drwxr-xr-x. 103 shs shs 36864 Could 6 11:43 . drwxr-xr-x. 25 root root 4096 Feb 17 11:36 .. -rw-r-----. 1 shs shs 66040 Jul 5 2022 4letters -rw-r-----. 1 shs shs 174 Jul 8 2022 4_vowel_words
You need to use the getfacl command to incorporate extra file entry permissions.
$ getfacl 5letters # file: 5letters # proprietor: shs # group: shs person::rw- person:popeye:r-- <===== group::r-- masks::r-- different::---
Discover that the command output above exhibits one person (popeye) who has learn entry to the file with out being a member of the related group or the file having entry permission for everybody.
Extra data on Linux permissions is offered at these pages:
Inspecting file content material
The cat, head and tail instructions will let you view file content material. Whereas cat will show the whole contents, you’ll be able to move the output to the extra command to view a screenful at a time. The head and tail instructions show strains on the high and backside of textual content information.
$ cat alert
REMINDER: This server will likely be shutting down @ 6PM tonight. Please end your
work by 5:45 and log out.
$ cat 5letters | extra
aahed
aalii
aalst
aalto
aamsi
…
$ head -5 4letters
1080
tenth
AAAA
AAAL
AAAS
$ tail -5 4letters
zuza
ZWEI
zyga
zyme
Zysk
You need to use the grep command to select strains that include some content material that you’re on the lookout for and nothing else. The grep command beneath shows solely strains that start with a “z”.
$ grep ^z 4letters | tail -5 zulu zuni zuza zyga zyme
Extra protection on the head and tail instructions may be seen on this head and tail instructions video.
The od command will show file contents in a really totally different vogue. It shows the characters together with their octal values – helpful for troubleshooting.
$ od -bc alert
0000000 122 105 115 111 116 104 105 122 072 040 124 150 151 163 040 163
R E M I N D E R : T h i s s
0000020 145 162 166 145 162 040 167 151 154 154 040 142 145 040 163 150
e r v e r w i l l b e s h
0000040 165 164 164 151 156 147 040 144 157 167 156 040 100 040 066 120
u t t i n g d o w n @ 6 P
0000060 115 040 164 157 156 151 147 150 164 056 040 120 154 145 141 163
M t o n i g h t . P l e a s
0000100 145 040 146 151 156 151 163 150 040 171 157 165 162 012 011 167
e f i n i s h y o u r n t w
0000120 157 162 153 040 142 171 040 065 072 064 065 040 141 156 144 040
o r ok b y 5 : 4 5 a n d
0000140 154 157 147 040 157 146 146 056 012
l o g o f f . n
0000151
Extra particulars on the grep command can be found at The numerous faces of grep
Viewing file entry occasions
The stat command shows the date of a file’s “start” and when it was final modified and final accessed.
$ stat 4letters File: 4letters Dimension: 66040 Blocks: 136 IO Block: 4096 common file Machine: 8,17 Inode: 3015994 Hyperlinks: 1 Entry: (0644/-rw-r--r--) Uid: ( 1000/ shs) Gid: ( 1000/ shs) Context: unconfined_u:object_r:user_home_t:s0 Entry: 2023-05-06 12:14:49.279689941 -0400 Modify: 2022-07-05 10:06:54.798552673 -0400 Change: 2022-07-05 10:06:54.798552673 -0400 Start: 2022-07-05 10:06:40.039362108 -0400
The date -r command will also be used to indicate a file’s final modification time, although it does so in a distinct format than the stat command.
$ date -r 4letters Tue Jul 5 10:06:54 AM EDT 2022
Wrap-up
A useful number of Linux instructions may also help you see something about information that you just wish to see. Strive the instructions on this put up and it’s possible you’ll discover they they’re much more helpful than you anticipated.
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