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What does the ampersand mean in Bash?
An ampersand does the same thing as a semicolon or newline in that it indicates the end of a command, but it causes Bash to execute the command asynchronously. That means Bash will run it in the background and run the next command immediately after, without waiting for the former to end.
What does an & after a command do?
The & makes the command run in the background. If a command is terminated by the control operator &, the shell executes the command in the background in a subshell. The shell does not wait for the command to finish, and the return status is 0.
What does ampersand mean at the end of a shell script line?
Yes, they are completely different. A && B means “run command B if command A succeeded”, and A || B means “run command B if command A failed”. Examples: ‘cd tmp && ls’ will run ls only if folder tmp exists. Or in a script: ‘cd foobar || exit 10′ will stop the execution (exit) if folder foobar doesnt’ exist.
What does & mean in redirection?
The & in 2>&1 simply says that the number 1 is a file descriptor and not a file name. In this case the standard output file descriptor . If you use 2>1 , then this would redirect errors to a file called 1 but if you use 2>&1 , then it would send it to the standard output stream .
What & Means in bash?
The & makes the command run in the background. From man bash : If a command is terminated by the control operator &, the shell executes the command in the background in a subshell. The shell does not wait for the command to finish, and the return status is 0.
Which is the shell redirection operator that will overwrite a file?
So, what we learned is, the “>” is the output redirection operator used for overwriting files that already exist in the directory. While, the “>>” is an output operator as well, but, it appends the data of an existing file. Often, both of these operators are used together to modify files in Linux.
What is the meaning of in bash?
(Entry 1 of 2) transitive verb. 1 : to strike violently : hit also : to injure or damage by striking : smash —often used with in. 2 : to attack physically or verbally media bashing celebrity bashing.