What is backslash in linux

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Quick Answer: What Does Backslash Do In Linux
Does backslash work on Linux?
What does backslash mean in terminal?
What does the backslash do in bash?
What does backslash mean in Ubuntu?
What is curl command Linux?
What is curl backslash?
What is forward slash in bash?
How do you BackSlash in CMD?
How do you escape a new line in shell?
What is quoting in Linux?
What is %q in printf?
What does Dquote mean in terminal?
Where is the backslash on the keyboard?
What is the use of line command?
What is semicolon in bash?
How do I curl in Linux?
Why is curl used?
How do I run wget on Linux?
How do I know if curl is installed?
How do I request curl in terminal?
Is curl part of Windows?
Recent Posts
Quoting Mechanisms in Linux
The Escape Character or Backslash
The Single Quotes
The Double Quotes
The Back Quotes

Quick Answer: What Does Backslash Do In Linux

A backslash escapes the next character from being interpreted by the shell. If the next character after the backslash is a newline character, then that newline will not be interpreted as the end of the command by the shell. It effectively allows a command to span multiple lines.

Does backslash work on Linux?

On any Mandriva GNU/Linux system the global aliases (for all users) are all in /etc/profile. Use a “\” (backslash) before the command to run it without the alias. \ (backslash) The backslash escape character can be used before a shell command to override any aliases.

What does backslash mean in terminal?

Escape characters are used to remove the special meaning from a single character. If a newline character appears immediately after the backslash, it marks the continuation of a line when it is longer that the width of the terminal; the backslash is removed from the input stream and effectively ignored.

What does the backslash do in bash?

A non-quoted backslash ‘ \ ‘ is the Bash escape character. It preserves the literal value of the next character that follows, with the exception of newline .

What does backslash mean in Ubuntu?

The backslash is used by bash to indicate a line continuation and is commonly used in bash scripts. However, the backslash is actually the bash escape character. So this use of the backslash ‘escapes’ the the \newline to create a continuation.

What is curl command Linux?

curl is a command line tool to transfer data to or from a server, using any of the supported protocols (HTTP, FTP, IMAP, POP3, SCP, SFTP, SMTP, TFTP, TELNET, LDAP or FILE). curl is powered by Libcurl. curl can transfer multiple file at once.

What is curl backslash?

The cURL examples often have a backslash (\) at the end of lines to break up a long statement into easier-to-read lines. The backslash is a line continuation character in UNIX but not in Windows. In Windows, replace any backslash at the end of lines with the caret (^) character, which is an escape character in Windows.

What is forward slash in bash?

In Linux and other Unix-like operating systems, a forward slash is used to represent the root directory, which is the directory that is at the top of the directory hierarchy and that contains all other directories and files on the system. Jun 25, 2006.

How do you BackSlash in CMD?

You can try holding down the “alt” key on your keyboard then pressing the “9” and “2” keys on the number pad. 92 is the ascii code for the backslash.

How do you escape a new line in shell?

Escape character ( \ ) can be used to escape end of line, e.g.

What is quoting in Linux?

Quoting is used to remove the special meaning of certain characters or words to the shell. Quoting can be used to disable special treatment for special characters, to prevent reserved words from being recognized as such, and to prevent parameter expansion.

What is %q in printf?

In addition to the standard formats, %b causes printf to expand backslash escape sequences (for example \n for newline), and %q outputs an item that can be used as shell input. The format string is reused if there are more items than format specs. Unused format specs provide a zero value or null string.

What does Dquote mean in terminal?

Description. DQUOTE( ) finds the first double quote mark in the string and returns all characters from that point, until a second double quote mark is found. If the string does not contain at least two double quote marks, a null string is returned.

Where is the backslash on the keyboard?

Creating the \ symbol on a U.S. keyboard It is located above the Enter key (Return key), and below the Backspace key. Pressing \ key creates a backslash.

What is the use of line command?

The basic function of the Command line is the ability to type keyboard commands. To type a command, place your cursor in the Command line and type that command. For example, if you want to draw a line, begin typing the word “Line” in the Command line.

What is semicolon in bash?

A semicolon or ampersand ( ; or & ) in a shell script is a command terminator. You can’t use it if it doesn’t follow a command. ; means “run the preceding command in the foreground” and & means “run the preceding command in the background”. A newline in a shell script is a “weak” command terminator.

How do I curl in Linux?

The procedure to install cURL on Ubuntu Linux is as follows: Update your Ubuntu box, run: sudo apt update && sudo apt upgrade. Next, install cURL, execute: sudo apt install curl. Verify install of curl on Ubuntu by running: curl –version.

Why is curl used?

curl is a widely used because of its ability to be flexible and complete complex tasks. For example, you can use curl for things like user authentication, HTTP post, SSL connections, proxy support, FTP uploads, and more! You can also do simple things with curl, such as download web pages and web images.

How do I run wget on Linux?

The wget package is pre-installed on most Linux distributions today. To check whether the Wget package is installed on your system, open up your console, type wget , and press enter. If you have wget installed, the system will print wget: missing URL . Otherwise, it will print wget command not found .

How do I know if curl is installed?

To check whether the Curl package is installed on your system, open up your console, type curl , and press enter. If you have curl installed, the system will print curl: try ‘curl –help’ or ‘curl –manual’ for more information . Otherwise, you will see something like curl command not found .

How do I request curl in terminal?

cURL POST Request Command Line Syntax curl post request with no data: curl -X POST http://URL/example.php. curl post request with data: curl -d “data=example1&data2=example2” http://URL/example.cgi. curl POST to a form: curl -X POST -F “name=user” -F “password=test” http://URL/example.php. curl POST with a file:.

Is curl part of Windows?

Windows includes a native curl.exe (and tar.exe ) in C:\Windows\System32\ , which you can access right from your regular CMD .

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Quoting Mechanisms in Linux

In Linux Shell, many special characters have their own special meanings. Sometimes they are used to perform an action while other times they are just used as a character, so the quoting mechanism performs this task it makes us use them in whatever way we want to.

Metacharacters: These are the special characters that are first interpreted by the shell before passing the same to the command. They are also known as shell wildcards.

$ Variable Substitution or expand the value of Variable.
> used for Output Redirection.
>> used for Output Redirection to append.
Input redirection.

* Match any number of characters, Substitution wildcard for zero or more characters

? Match one character, Substitution wildcard for 1 character

[] Match range of characters, Substitution wildcard for any character between brackets

`cmd` Replace cmd with the command to execute and will execute that, Substitution wildcard for command execution

$(cmd) Replace cmd with the command to execute and will execute that, Substitution wildcard for command execution

| Pipe is a Redirection to send the output of one command/program/process to another command/program/process for further processing.

; Command separator is used to execute 2 or more commands with one statement.

|| OR conditional execution of the commands.

&& AND conditional execution of the commands.

() Groups the command in to one output stream.

& executes command in the background and will display the assigned Pid.

# to comment something.

$ To expand the value of a variable.

\ used to escape the interpretation of a character or to prevent that.

The Escape Character or Backslash

A Backslash(‘\’) is the bash escape character. Any character immediately following the backslash loses its special meaning and any letter following the backslash gains its special meaning. Enter the following commands in the terminal.

echo "Quotation" echo \"Quotation\"

As it can be seen with the example that double could be not printed without backslash and with backslash as they lost their special meaning, so they were printed.

The Backslash Escaped Characters

\a alert (bell)
\b backspace
\e an escape character
\f form feed
\n new line
\r carriage return
\t horizontal tab
\v vertical tab
\\ backslash
\’ single quote
\nnn the eight-bit character whose value is the octal value nnn (one to three digits)
\xHH the eight-bit character whose value is the hexadecimal value HH (one or two hex digits)
\cx a control-x character

The Single Quotes

Single Quotes(”) are used to preserve the literal value of each character within the quotes. A single quote may not occur between single quotes, even when preceded by a backslash. All special characters within the single quotes lose their special meanings.
Some strings have a lot of special characters so it is hard to use a backslash before every special character. Hence, if we will put the same string within single quotes, most of the special characters will lose their special meanings. Enter the following commands in the terminal.

You can be seen from the example that we had to use a lot of backslash in the first statement which made it complex. While with single quotes output was same without using backslash

The Double Quotes

Double Quotes(“”) preserves the literal value of all characters within the quotes, with the exception of ‘$’, ‘`’, ‘\’, and when history expansion is enabled, ‘!’. The backslash retains its special meaning only when followed by one of the following characters: ‘$’, ‘`’, ‘”’, ‘\’, or newline. Enter the following commands in the terminal.

name=geeksforgeeks echo '$name' echo "$name"

You can be seen that in the case of single quotes the value of the variable was not printed while in the case of double quotes the value of the variable was printed.

The Back Quotes

Back Quotes(“) are used to execute a command. Anything enclosed between them will be treated as a command and would be executed. Open the terminal and execute the following commands.

hostname=`hostname` echo $hostname

You can be seen from the example the hostname command gets executed and the name gets stored in the variable.

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