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tcsh - understanding difference between "echo string" and "echo string > /dev/stdout"

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http://www.unix.com – I came across and unexpected behavior with redirections in tcsh. I know, csh is not best for redirections, but I'd like to understand what is happening here. I have following script (called out_to_streams.csh): Code: #!/bin/tcsh -f echo Redirected to STDOUT > /dev/stdout echo Redirected to STDERR > /dev/stderr echo Should default to STDOUT without redirection When I pipe the output like this: Code: ./out_to_streams.csh | vim - I get "Redirect to STDOUT" and "Should default to STDOUT without redirection" being piped. When I redirect to a file: Code: (HowTos)

Shoutmeloud's picture
Submitted by Shoutmeloud on 07/09/2012 – Made popular on 07/09/2012

Stories similar to tcsh - understanding difference between "echo string" and "echo string > /dev/stdout"

Is there a way in Windows 7 cmd shell to redirect the stderr to stdout while keeping the stderr stream intact?

For example, I have a program that outputs to stderr and stdout the following message

TO STDOUT TO STDERR

I want to have two files stderr.txt and stdout.txt with the following content

stderr.txt TO STDERR

stdout.txt TO STDOUT TO STDERR

Is this possible?

Apart from the standalone exec >&2 to redirect the current shell's input and output are there any behavioral differences in the following commands:

echo -en "C\nB\nA\n" | sort 2>/dev/stdout >&2 echo -en "C\nB\nA\n" 2>/dev/stdout >&2 | sort 2>/dev/stdout >&2 echo -en "C\nB\nA\n" | sort

If the above commands were equivalent which is the preferred variant?

I'm trying to redirect the output of the constructor of an object that is created by a shared library to /dev/null.

I have a C program that continously outputs info to stdout. The problem is that I am redirecting the stdout and stderr to a file and stdout is written at the end of the problem rather than continously to the file. This could be a problem if for example the program is killed and the stdout output is lost.

How I can accomplish STDOUT to be to logged in a file (appending), but preserving the flow (leave STDOUT to STDOUT) ?

STDOUT should work transparently, but should be logged also into a file, without messing with "tee" on each command input. Same for STDERR.

Simply, mirror output to file.

I'm trying to hack in better logging for a test program that I didn't write. I want all lines of STDERR output to have timestamps, but if possible I want to leave STDOUT alone.

As part of a continuous delivery pipeline I'd like to install an msi on a given machine.

I have a script a.sh, which has an sftp command:

echo "Starting to sftp..." sftp xxx@xxx.xxx.xxx.xx << END_SCRIPT ls mput *.csv.gz bye

END_SCRIPT echo "Sftp successfully."

If I run it interactively, the log output from sftp is shown. However, if I set it in a crontab and redirect the stdout to a file using >, there will be only the output from the two echo statements.

I piped my own shell scripts for some testing and accidentally noticed something strange.