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).
Which of the following will ensure that STDOUT and stderr are redirected to the same file?
To redirect stderr and stdout , use the 2>&1 or &> constructs.
How do I redirect STDOUT and stderr to a file in bash?
Bash executes the redirects from left to right as follows:
- >>file. txt : Open file. txt in append mode and redirect stdout there.
- 2>&1 : Redirect stderr to “where stdout is currently going”. In this case, that is a file opened in append mode. In other words, the &1 reuses the file descriptor which stdout currently uses.
How would you redirect output from stdout to a file?
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 append a file in bash?
How to append to file in Bash. To make a new file in Bash, you normally use > for redirection, but to append to an existing file, you would use >> . Take a look at the examples below to see how it works. To append some text to the end of a file, you can use echo and redirect the output to be appended to a file.
How do you append the output of a command to a file in Linux?
How to redirect the output of the command or data to end of file
- Append text to end of file using echo command: echo ‘text here’ >> filename.
- Append command output to end of file: command-name >> filename.
How do I append to a file in Bash?
How to append to file in Bash. To make a new file in Bash, you normally use > for redirection, but to append to an existing file, you would use >> .
How do you append standard output with redirection operator?
The append >> operator adds the output to the existing content instead of overwriting it. This allows you to redirect the output from multiple commands to a single file. For example, I could redirect the output of date by using the > operator and then redirect hostname and uname -r to the specifications.
Which of the following commands redirects its standard output to the file stdout and redirects its standard error to the file stderr?
Conclusion
| Operator | Description |
|---|---|
| command>filename | Redirect stdout to file “filename.” |
| command>>filename | Redirect and append stdout to file “filename.” |
| command 2>filename | Redirect stderr to file “filename.” |
| command 2>>filename | Redirect and append stderr to file “filename.” |
Which character’s would you use to redirect standard output to append to a file called output txt?
You need to use the >> to append text to end of file. It is also useful to redirect and append/add line to end of file on Linux or Unix-like system.
How to append to a file in Bash?
How to append to file in Bash. To make a new file in Bash, you normally use > for redirection, but to append to an existing file, you would use >>. Take a look at the examples below to see how it works. To append some text to the end of a file, you can use echo and redirect the output to be appended to a file.
How do I redirect the output to a file?
The > operator redirects the output usually to a file but it can be to a device. You can also use >> to append. If you don’t specify a number then the standard output stream is assumed but you can also redirect errors
How to redirect stderr to another file in Bash?
>>file.txt: Open file.txt in append mode and redirect stdout there. 2>&1: Redirect stderr to “where stdout is currently going”. In this case, that is a file opened in append mode. In other words, the &1 reuses the file descriptor which stdout currently uses. Show activity on this post. There are two ways to do this, depending on your Bash version.
How to redirect stdout from command line in Linux?
command >> file to redirect just stdout of command. command >> file 2>&1 to redirect stdout and stderr to the file (works in bash, zsh) sudo command >> /file/requiring/sudo/privileges does not work, as privilege elevation applies to command but not shell redirection part. However, simply using tee solves the problem: Show activity on this post.