There are the following quotes:
Double quote
" "
Is placed between Double quote text that the values of variables that contain spaces.
Quotes retain special meaning three characters:
$ - indicates the name of a variable, allowing the substitution of its value
\ - a placeholder
` ` - reverse apostrophe, citing command allows
Example
#/bin/bash
x=2
echo "The x value is $x" # prints the value of the variable x= 2
echo -ne "You will hear a bell\a"
echo "The date command shows:`date`"
x=2
echo "The x value is $x" # prints the value of the variable x= 2
echo -ne "You will hear a bell\a"
echo "The date command shows:`date`"
Single quote
' '
Everything included in the single quote character is treated as a text string to interpret the apostrophe off all special characters are treated as regular characters.
Example
#/bin/bash
echo '$ USER' #do not print your login
echo '$ USER' #do not print your login
Backquote
` `
command allows you to quote, very useful if you want to substitute the variable outcome of a command such as:
Example
#/bin/bash
x = `ls -la $ PWD`
echo $ x # shows the result of the command
x = `ls -la $ PWD`
echo $ x # shows the result of the command
Alternative record of who has the same effect like this:
#/bin/bash
echo $ (ls-la $ PWD)
echo $ (ls-la $ PWD)
Backslash
\
To appear $HOME, you can write it in quotes but you can also mask the first of his character, as shown in the example.
Example
echo "$HOME" # prints /home/me
echo \$HOME # and is the $HOME
echo '$HOME' # and the $HOME
echo \$HOME # and is the $HOME
echo '$HOME' # and the $HOME
Putting a backslash \ at the end of the line tells the shell that the line is continued on the next line (normally the next line is the next instruction). This eliminates the need to write long poems, which interfere with the convenient editing and viewing a file (not all editors support automatic wrapping).
Local documents
Llocal documents
This is the kind of redirect, which allows some content to treat the script as standard input.
Example:
#/bin/sh
cat << _EOF
This text will be
displayed on the screen
limiter is _EOF
_EOF
cat << _EOF
This text will be
displayed on the screen
limiter is _EOF
_EOF
After running the script on the screen get everything that we entered into between _EOF. This method can be used to display more information on the screen without having to type echo in each line.
Important: The final stop needs to find himself in one line. Delimiter can be any expression, but most often used is "_EOF".