Q. How do I redirect stderr to stdout? How do I redirect stderr to a file?
A. Bash and other modern shell provides I/O redirection facility. There are 3 default standard files (standard streams) open:
[a] stdin - Use to get input (keyboard) i.e. data going into a program.
[b] stdout - Use to write information (screen)
[c] stderr - Use to write error message (screen)
Understanding I/O streams numbers
The Unix / Linux standard I/O streams with numbers:
| Handle | Name | Description |
| 0 | stdin | Standard input |
| 1 | stdout | Standard output |
| 2 | stderr | Standard error |
Redirecting the standard error stream to a file
The following will redirect program error message to a file called error.log:
$ program-name 2> error.log
$ command1 2> error.log
Redirecting the standard error (stderr) and stdout to file
Use the following syntax:
$ command-name &>file
OR
$ command > file-name 2>&1
Another useful example:
# find /usr/home -name .profile 2>&1 | more
Redirect stderr to stdout
Use the command as follows:
$ command-name 2>&1
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{ 5 comments… read them below or add one }
What this mean?
$ command > file-name 2>&1
Sayed: that line means execute the command while redirecting both stdout and stderr to a file given by file-name.
Greetings!
A slightly more correct is:
The output of the ‘command’ is redirected to a ‘file-name’ and the error chanel (that is the ’2′ is redirected to a pointer (?) of the output (‘&1′).
So stderr goes to the stdout and that goes to the file.
RudyD
+1
:)
I like the &>file one. but not for every stiuation.