UNIX/Linux - Basic Commands | UNIX Tutorial | Mr. Subba Raju

welcome to nourish a technologies this is Subba Raju and we are going to discuss in this session UNIX files and their colors in UNIX operating system we'll try to identify each and every file with the help of the related color for example dark blue or blue we are calling as a directories and I displayed already on the television set you can try to view that next one is green is nothing but executable files next one is sky blue linker files yellow is all these are calling as device related files pink color image related files ready color zip files or compressor files these are the colors easy to recognize each and every file in the UNIX operating system on the black console if you come to UNIX file notations each and every symbol is giving one proper meaning for example we can try to see that and bottom I wrote the first one at the rate or at we are calling as link profiles astrick represents as executable files - represent ordinary or regular file d directory l linker files mainly symbolic link small s socket related files and P pipe related files like this if you are using black and white monitor we can recognize with the help of symbols if you are using color monitor we can recognize with the help of colors so UNIX is so much sophisticated for backward level people as well as for world level also because why I'm saying sophisticated if you are using black and white also we can recognize if you are using colorful montes also we can easily recognize the file system right come down to other thing basic commands I need to start before I am entering into UNIX basic commands what is a command command is an executable program or pre compiled program every command is NEX e it is an instruction to the operating system there are various commands the UNIX operating system try to view in this session basic level commands in that basic level command first I wrote here who and remember in UNIX operating system all commands are case sensitive but before entering into comments also I am giving a few instructions related to commands every command should be in lower case all commands should be started with alphabet character command should not a contains any unnecessary special characters all commands or keywords or reserved words these are the instructions related to Unix commands will try to view on the console of the UNIX operating system come to already install the console I am opening in front of you and how to install and how to configure users and I will show you separately this UNIX operating system in a separate video session now I am showing to you basic commands this is root folder or root directory by typing PWD present working directory you want to zoom in control shift to plus plus you can do zoomin PWD present working directory or current working directory it is always representing where you are located and LS is the list related to this command in another video session we can say first LS means it is displaying all the files and directories names which are available in the current location you are seeing here dark blue related directories directory always in dark blue if you want to change a directory whatever the colors are shown to you too to CD you can go to the related directory bin and enter press LS different kind of files you can view here for these files representation already explained very clearly starting of this video and again you want to come out from there CD space double dot change directory and come out again I want to see another one de V device again LS see the different different colors what I represented already in the UNIX operating system again CD double dot and CL e AR another command to clear the console and I am pressing enter clear the console and CD home where exactly the users list available here users list available if you want to change to any user you can press the related name directly and CD Raj because it is not giving any permission to change so Raj is not created by me that is a reason it is saying para mission denied so you need to know whichever the user you created only that user you can try to enter observe I am showing various various areas finally I am selecting my one and Raj five so like this this this meaning various various uses because you observe are not I logged in with the Red Hat actually so Red Hat is my user so I am going to that Red Hat observer now it is accepting so why access denied these are the other users I am not logged in with those users which use I logged in with the Red Hat come on LS here and Red Hat inside available here again I am going to my personal directory is called Raj and I am showing inside the files whatever available these are the directories inside the Rose shell programming Perl programming and whatever the requirement of the nodes available are related come out from the CD double dot space is there between CD and embedded characters or periods and again I can say CD now I am working in this directory and flexible purpose these are the information available now PWD you can say present working directory right now my current directory is NIT inside the NIT several files available if you want to go to again under a directory CD hi available you file so now I am discussing about UNIX files what is a file it contains the related data or information in the UNIX operating system files are classified into three types number one normal files or regular files second one directory files third one special files or device files previously shown already some special files to you those are different different colors available all these colors maximum except black or white and remaining all related colors or relay related to user level now I can show you some kind of files creation and how the file system is working here observe first command I am showing to you already prepare that one to show each and every command that is only who command who command who is saying currently how many users are logged in using who command we can display currently which users are logged in only one user login the user name is Red Hat with the two terminals it is showing that I explained to you now Who am I is another command it is giving directly the user who is logged in logged in by a Red Hat and here only we can display this name with the help of log name command also that is all so rather hat now one by one commands we can try to view elaborated for example if you are going to any command a little bit more information use one powerful command is called a man man is nothing but a manual which is providing online manual pages information nothing but help whatever information you require related to Unix any command any statement including shell and Pole everything available with this valuable man command for example I required some information related to who and a man who enter now and it is displaying completely related to who show login is who is logged on and who option and arguments available and displaying the information plus several kind of options also coming on your screen so every option we can try every option we can see once you view all these options then you want to come out from here Q is nothing but quit from manual section this is the command here now who command for example I am using who space I want to know currently how many users are logged in and already man command is in front of you and observe once you are coming to man common currently how many users logged in you want to see the list means it displays - Q or - - count all login names and the number of users logged on so it is going to display that option and what is the process currently running and for example you are going to use that I am showing to you how to use option who space - and you can type whatever the option you required are iPhone iPhone count you can say it is showing to users because Red Hat already installation time one user available I created separately under user so number of users - it is showing and this is comes under installation admin this is a separate user - users it is showing to you and if you are coming to again this you want to display that and simply you can say how many uses how many deadlocks available here no deadlocks available and it is showing to you last system boot started so-and-so system so my system switched on today morning 10:17 a.m. it is showing very clearly time on that one like this who is the command mainly to display how many users currently logged in so next command is useful command frequently we are using that is Cal who displays calendar just you can try to observe current a month it is a display depends on your system date and time settings if not displaying command proper output check your system date and time settings and displayed current and for example Carol related options you want to view just man and go for the Cal Cal means not calculator it is a calendar in the UNIX operating system and click on that and again you are having some Cal options yes m j y and 1/3 I will show you what is that day month year and if you are coming to options one by one - one by D single month output - three three months previous current next month output will be displayed - s a displaced Sunday is the first day of the vehicle yes if you are seeing as per the civil calendar or Christian calendar Sunday is the first day of the week Saturday is the last day of the week if you are displaying - s means Sunday - as unit type is a default of feature if you want a Monday - M is the Monday is the first day of the week and if you come down to J Julian calendar Julian calendar sense no months completely years available that means of in your year 365 days available total days it is displaying for example we are in eighth month already seven months completed on an average week and almost all 200 nearly 25 is completed like that if you type maybe today right we'll type that one and we'll check it what IB swim Cal - Jay and Julie and displaying today is 237 in 365 days calendar so it is displaying always add a number without any month right Cal already said - one default one month without - one also previous output you can observe by default one month only displayed and Cal - one and next one Cal - three maybe screen not adjusted will come to control - to get the better output please try to view now right previous current next month output so like this next one total your calendar you want to see Santa coming first by default I said already sunday is the default sunday is the first day of the week no I want Monday right you want Monday means right zoom in Cal - M and it is displaying Monday is the first day of the week and I want total year calendar Cal - why observe please total ear calendar it is a total ear calendar like this Cal command providing almost all all options related to calendar next we can try to view another command is called date date also bigger command it is also having several options if you press directly without any arguments and expressions and date by default providing short form Wednesday and a guest and it is giving 24 and the date is the Indian Standard time and it is giving completely so as per that if you are going to date the related commands you want to see + % age small a it displays the day in short form and if you are giving capital a the day in full-form if you are giving small be month in short form if you are giving capital be month in full form like this you are having 27 to 30 options you want to see those are closer man and a debt command observe in detailed information clearly available not only get the state and time even you can set also I will show that one also date the plus format and if you are coming - D - f and percentage kind of information you want to see related to that small a and capital a small B capital B like this 27 options available here some more options if you want to view come back for example I am typing here date date plus percentage I am giving capital f YY mm D D for example capital t hours minutes seconds for example you are giving small I here in short form capital y here in full form this is about date all these are basic level commands to come to I said already in UNIX operating system files are classified into three types we can try to observe first type normal files or ordinary files how to create these normal files how to execute these normal execute neces how to display these normal files on the screen one by one we can try to observe here color is black black or white if screen is white color is black normal file if screen is black file is white normal file by default normal files available black color these are called - symbol notation you want to see that - symbol just LS - L if you press first notation is giving to you normal file the remaining things will see in the later sessions first will to understand normal file or our file how to create these files one by one we can try to observe simply there is a command available cat concordance can coordinate in the sense we are creating cat can do 3 Duty's Duty number 1 creating a file duty number 2 displaying the file contents 3rd duty is appending the file one by one we can write observe cat cat first we need to create a file before that how to view cat related information Man cat and available can coordinate files on standard output the sense monitor or screen we are calling cat option file name come down options to view - capital a - - show - all never say - guys only - - B - - number - - non blank number non empty output lines and come down - e equivalent to capital small V capital e I will show you that one capital - E and - - show - ends so one by one all these options will try to view and Q quit from there and right now only one file available I am creating another file cat this is we are calling as standard output redirection 'l operator and I am giving filename here nowadays technologies simple and whenever I am providing arrays technologies name so this is standard output redirection allow it is not greater than we should not use mathematical language here right press Enter once you entered the prompt is allowing you to enter the data prompt means user interface now I am entering welcome to nourish technologies you with unique sessions narae's technologies unix sessions unix sessions enter whatever the lines of data you require whatever the lines of if you want to save ctrl + d save and it controlled e-file saved and exit to the prompt this is called prom dollar is the user prompt remember hash is the admin prompt we are the user available in front of the dollar now I want to view the file created or not LS what is LS latter session we can see LS nourish technologies nit so this is already created file recently created this one I want to view these file contents definitely cat standard input redirection all operator standard output redirection 'l operator standard input redirection 'l operator hit the return key once you hit the return key whatever the data you type your same data are displayed but always standard input redirection operator not compulsory view this command without redirection operator I am typing enter fine you can see my output very clearly so that means input redirection operator is optional where it is mandatory we'll see in couple of minutes now next we can try to observe options once you are going to options in the cat command first cat and nourish technologies let me open that and here how many lines available three lines available this is also data this is also data this is also data so three lines available how can I see that one cat - n narae's technologies file name yes in your file three lines of data available it displayed for example you are going to append this file I said already cat doing three Duty's Duty number one creating s we did already displaying the contents we did now third one I am going to appending your file what is append append is nothing but adding some more data to an existing file in the existing data is called append how I'm appending you can write observe cat and append upendra directional upper later and I am giving filename is nourished technologies yes provide the filename there narae's technologies once you provided hit the return key there is technologies yes and it is allowing to append I am writing I am appending appending ni t5 narae's technologies for anywhere you can write that is technology file yes you are appending that enter ctrl D ad number of lines can enter ctrl D means save and exit now really appended or not you want to view yes provide the command of write append means it is adding the data to an existing file under existing data it is appended so append VDP completed now I want to open once again I want to append with the two empty lines observe now I am giving Kath - n number of lines available total six lines last two lines empty no I do not want these two empty lines then you can provide line numbers only for the data lines then B B means only for the non blank lines output is coming so this is the cat command cat related options thank you for watching my videos we'll continue this session in the next video

Channel: Naresh i Technologies

Views: 393,138

Keywords: Unix/Linux, Subba Raju, OS, Naresh IT, Hands on UNIX/LINUX Training, UNIX Demo, Online UNIX Training, UNIX Tutorial Videos, UNIX Overview, UNIX Interview Questions, Basic Commands, Linux Basic Commands, Unix Basic Commands, Subbaraju, learn linux basic commands, linux commands, unix shell commands, UNIX, unix, linux

Id: SfZ567IlInw

Length: 24min 5sec (1445 seconds)

Published: Fri Aug 26 2016