How to open a text file in linux
The common functionalities are the following: Format output lines Transforming data files Scanning files per line Splitting input line into fields (There are several options all starting with -M where you can define where to write which dependencies — this invocation is independent from later compilation, no code/object files will be generated is just parsing of the deps) Solution 1: In Ubuntu exist a command called xdg-open , that opens a file or URL in the user’s preferred application, so you can open several types of files with the default program pre-defined.
How to open the default text editor in Linux?
There is no completely reliable concept of «default editor» on Linux, let alone more broadly Unix-like systems.
Traditionally, users would set the environment variable EDITOR to the path of their editor of choice. If this variable is set, I’m thinking you can be reasonably confident that they will know how to use it, even if they end up in something horrible like nano .
A slightly newer convention is to set VISUAL to the preferred «visual editor» — I guess the terminology comes from vi to contrast against line editors like ed .
On Debianish systems, the system default editor is configurable via alternatives and available simply with the command editor .
On XDG systems, of course, you could simply
touch path/to/new/file.txt xdg-open path/to/new/file.txt Needless to say, this only works if you have XDG, i.e. In practice a Linux (or maybe modern *BSD) platform with an active graphical session (excludes Mac and pre-XDG graphical systems as well as of course any server environment where there is no GUI).
As an aside, if I can guess even roughly what your script does, it could probably be pared down to a fairly simple sed script. Remember, sed can do (almost) everything grep and tail can. Maybe see also Combining two sed commands — here is a quick and dirty refactoring.
cd /usr/share/applications $(sed -n "s:^Exec=\([^%]*\)\(%.\(.*\)\)*:\1\3:p" "$(sed -n "s:^$1=::p" defaults.list | tail -1)" | tail -1) & However, from quick googling, it looks like /usr/share/applications/defaults.list is specific to OpenDesktop environments; but it’s the system-wide default default — the admin could have installed an override in a different location, and individual users probably have individual preferences on top of that. Finding and traversing this hierarchy is precisely what xdg-open does, so I’m not going to try to reimplement it in an ad-hoc script of my own, and suggest you shouldn’t, either.
There is nothing about graphical environments in your question, so it’s unclear whether you are actually looking for a simple editor for beginners who barely know how to click and drool in a graphical environment (in which case I’d say go with touch followed by xdg-open ) or a competent programmers’ editor which way or may not run in a window (maybe try VISUAL with fallback to EDITOR , and document that you use this mechanism).
Is vi your default editor? i would do something like «vi mynewfile.txt»
How to Edit Text Files Graphically on Linux With gedit, To open an existing text file click the “Open” button in the gedit toolbar. You can also press Ctrl+O to open a file. This opens the recent files menu. If you want to re-open one of the listed files click on the name of the file. If you wish to open a different file, click the “Other documents…” button at the …
Linux shell command to read text file and open documents listed within
You know -M flag of gcc ? (There are several options all starting with -M where you can define where to write which dependencies — this invocation is independent from later compilation, no code/object files will be generated is just parsing of the deps)
How to Run Bash Commands From a Text File, Using bash. Let’s consider we have a file called sample.txt, which includes one echo command and a variable set: $ cat sample.txt echo «Hello World!» var= «variable is set». We can run our file by using the bash command: $ bash sample.txt Hello World! bash reads the file content and executes it in the …
Open default text editor from terminal
In Ubuntu exist a command called xdg-open , that opens a file or URL in the user’s preferred application, so you can open several types of files with the default program pre-defined.
xdg-open hello_word.tiff Open the file using the default image visualizer.
xdg-open Template.odt Open the file using with LibreOffice.
xdg-open myfile.txt Open the file using gedit (Text editor).
By my knowledge the xdg-utils are already installed in Red hat.
For the users who got here by Google search looking for a different answer, who want want to stay in the terminal: check to see if there’s a defined editor, then try something else, like nano file , or use xdg-open file as a less portable fallback.
if [ -z $ ]; then xdg-open myfile.txt; #from Luis's answer above else $EDITOR file.txt; fi How to open a text file from terminal?, If the goal is to read a text file from the command prompt, and be able to scroll the text, then most *NIX systems have the utilities less or more that can be used. robert@pip2:/tmp$ less exampleText.txt. If you just want to spew the text to the command line, then try cat. robert@pip2:/tmp$ cat exampleText.txt.
Gawk Scripting Usage Examples
One way of working with files in Linux is using a scripting language to manage the automation of repeated tasks. An example of a good scripting language is awk which makes the extracting of data and working with patterns easy. The GNU implementation of the awk scripting language is gawk. If you are yet to come to terms with its usage, you are in luck. This post presents the different examples of the use of gawk in Linux, and by the end of this guide, you will have a solid understanding of working with it.
Getting Started with Gawk
If you are using the latest Linux versions, gawk should be installed by default. You can verify by checking its version.
There are different ways to use gawk. The common functionalities are the following:
- Format output lines
- Transforming data files
- Scanning files per line
- Splitting input line into fields
- Producing formatted reports
- Sorting data
The basic syntax for gawk is:
$ gawk [ POSIX / GNU style options ] -f program_file [ — ] file
$ gawk [ POSIX / GNU style options ] [ — ] ‘program’ file .
To use gawk, you either use the -f option to specify a script file or specify the script on the command line directly.
There are three important options to note when using gawk:
1. -f file, –file=file: Used when you want to use gawk and read commands from a file. The file is the script.
2. -v var=val, –assign=var=val: Used when you need to assign a value to a variable before executing a script.
3. -F fs, –field-separator=fs: The value of the predefined variable FS gets used as the separator for the input field.
Built-In Variables
Gawk offers built-in variables such as:
FS: Used when dividing files and contains the field separator character.
RS: Contains the current character separator.
OFS: Contains the output field separator that separates the fields that AWK prints.
NF: The number of fields for the input record gets stored in the NF.
ORS: Contains the output field separator that separates the output lines printed by AWK.
NR: Contains the total number of input lines.
In the previous example, we use * as the separator for the input lines in the file.
Example Usage of Gawk
1. -F
For sorting a text file and printing the first three colon-separated fields, use the following command. Note that we use the passwd as our file here:
Here, our separator is a full colon. Since we want the first three fields, you specify them as shown in the previous example. You can tweak it around and use a different separator and a different number of fields.
2. -f
To specify the awk program source from a file, use the -f flag followed by the file:
3. Printing Contents of a File
Using gawk on a file prints all the data lines in the file.
4. Working with Patterns
You can also use gawk and print only the lines matching a given pattern. For instance, to print a line containing a particular word, in our case the word is kim , the command would be:
Here, the pattern can also be a character. For instance, to print all the lines that contain a colon, the command would be as in the following image:
You can also specify the specific lines to print. For instance, to print the lines containing specific characters such as greater than 6, the syntax is:
5. Splitting Lines Into Fields
Gawk, by default, prints every field when printing lines in a file. However, you can specify which field to print. The first field gets stored in the $1 and the whole line is represented as $0. By default, the entire line gets printed unless you specify to separate the fields based on the whitespace.
For instance, to separate the lines and print only the second field of each line, the command would be:
To add the line numbers, add the NR variable.
6. Get the Number of Lines
You may need to get the total number of lines for large files, and you can achieve that using the following syntax:
Conclusion
Knowing how to use gawk in Linux is fun and helpful, especially when dealing with text data. You can use the different patterns to extract and manipulate the lines of data. Hopefully, the examples covered in this article give you a head start and open your eyes in using gawk for different activities.
How to open the file in bash, Use of `cat` command: The `cat` is a very useful command of bash to create or display the file’s content. Any file type can be created easily and quickly by opening the file using the `cat` command with the ‘>’ symbol. Run the following `cat` command to open a file named file1.txt for writing.