What is >& 2 in shell script?

and >&2 means send the output to STDERR, So it will print the message as an error on the console. You can understand more about shell redirecting from those references:

What is stdout in Unix?

Standard output, sometimes abbreviated stdout, refers to the standardized streams of data that are produced by command line programs (i.e., all-text mode programs) in Linux and other Unix-like operating systems. That default destination is the display screen on the computer that initiated the program.

What does Unix tee do?

The tee command in UNIX is a command line utility for copying standard input to standard output. It supports writing whatever it is given from standard input to standard output and optional writing to one or more files. The command is named after T splitter used in plumbing.

How do I redirect to stdout?

2 Answers

Redirect stdout to one file and stderr to another file: command > out 2>error.
Redirect stdout to a file ( >out ), and then redirect stderr to stdout ( 2>&1 ): command >out 2>&1.

How do you use the tee command?

Use tee followed by any number of files to write the same output to each of them: [command] | tee [options] [filename1] [filename2]… The ls command shows that tee successfully created files example1. txt and example2.

What is $# in shell script?

$# : This variable contains the number of arguments supplied to the script. $? : The exit status of the last command executed. Most commands return 0 if they were successful and 1 if they were unsuccessful. Comments in shell scripting start with # symbol.

What exactly is stdout?

Stdout, also known as standard output, is the default file descriptor where a process can write output. In Unix-like operating systems, such as Linux, macOS X, and BSD, stdout is defined by the POSIX standard. Its default file descriptor number is 1. In the terminal, standard output defaults to the user’s screen.

Where do I find stdout logs?

\logs\stdout” in your web. config file, the logs directory should be created next to the web. config, inside the publish directory. To create the logs subdirectory you can use the approach described in the ASP.NET Core directory structure.

How does tee work?

In computing, tee is a command in command-line interpreters (shells) using standard streams which reads standard input and writes it to both standard output and one or more files, effectively duplicating its input. It is primarily used in conjunction with pipes and filters.

Does tee append or overwrite?

By default, the tee command will overwrite the file with the output of the initial command. Which can be overridden by using an append option using -a switch. Like with standard commands appending with >, the errors and stdout are handled differently in tee as well.

How do I add stdout to a file?

1 Answer

Either use this construct: cmd >>file. txt 2>&1 where >> file appends the output to the file and 2>&1 redirects the stderr to stdout .
Or use cmd &>>file ensuring that you have bash version >4 (using bash –version ) and #!/bin/bash at the beginning of file ( #!/bin/sh won’t work).

What is Unix PG command?

pg is a terminal pager program on Unix and Unix-like systems for viewing text files. It can also be used to page through the output of a command via a pipe. pg uses an interface similar to vi, but commands are different. Users are expected to use other paging programs, such as more, less or most.

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