Tee standard output bad file descriptor

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Create a free Team What is Teams? Learn more. Output tee to stdout while writing to a FD using here-strings Ask Question. Asked 1 year, 5 months ago. Active 1 year, 2 months ago. Viewed times. I am trying to output tee while writing to a custom file descriptor. I am using BASH 5. Thanks a lot! Improve this question. Add a comment. Active Oldest Votes. Improve this answer. Thanks for your explanation.

This also seems to work just fine with name file descriptors, e. I feel like 1. I did edit my comment in the mean time. If that function failed, then there is nothing to restore - the very last operation is setattr. ALL thanks for looking into it. I have the same issue when I started with cmd instead of powershell. I had the same issue on my first installation with mingw64 directly no miniconda with the bash shell.

I did run the test with Modelsim It's a minor issue because the internal simulations are working okay. It would be nice to have a clean output in the build artefacts when we have to track down a failed test. I'm impressed by all the work team cocotb is doing. Writing tests with python is much more pleasant and easier to track. The separation of the test form the framework may allow us to switch simulators in the future.

I just tried running Questa on Linux and it does reopen the streams with buffering successfully. One last thing to try is run the vsim command that runs the simulation on the command line directly, and not within vsim as the makefile does.

If you have already built the library you can run:. The output on the powershell is:. But then it stops the execution without return to Modelsim or Powershell shell. I had to close the Shell window. See sim. It looks to me like the difference between good vs bad is whether modelsim prints the following before or after our logging starts:.

Lines to in dd If these fail, we could try fprintf stderr, "Could not write to stdout! Has your question been resolved? This is useful when you have a lot of output that is difficult to read on the screen or when you want to put files together to create a larger file. Though not used as much as output redirection, the input for a command, which normally comes from the keyboard, can also be redirected from a file. This is known as input redirection. Redirection of input lets you prepare a file in advance and then have the command read the file.

Any command that outputs its results to the screen can have its output sent to a file. For example, to send the results of the who command to a file called users , enter:. For example, to send the current directory listing to a file, enter:. For example, to append file2 to file1 , enter:. The cat command alone takes whatever you enter at the keyboard as input. You can redirect this input to a file.

Enter Ctrl-D on a new line to signal the end of the text. Combining various files into one file is known as concatenation. The previous example creates file4 , which consists of file1 , file2 , and file3 appended in the order given. The following example shows a common error when concatenating files:. For example, to send the file letter1 as a message to user denise with the mail command, enter:. This file has a unique property; it is always empty.

This is a useful feature when you run a program or command that generates output you want to ignore. For example, you have a program named myprog that accepts input from the screen and generates messages while it is running that you would rather ignore.

To read input from the file myscript and discard the standard output messages, enter:. In this example, myprog uses the file myscript as input and all standard output is discarded. In addition to the standard input and standard output, commands often produce other types of output, such as error or status messages known as diagnostic output. Like standard output, standard error output is written to the screen unless redirected. Generally, when a command starts, three files are already open: stdin standard input , stdout standard output , and stderr standard error.

However, if you want to redirect standard error or other output, you must use a file descriptor. File descriptors can also be specified to redirect standard input and standard output, but are already the default values. The following numbers are associated with standard input, output, and error:.

For example, the following command takes the standard error output from the cc command where it is used to compile testfile. Other types of output can also be redirected using the file descriptors from 0 through 9. For example, if the cmd command writes output to file descriptor 9, you can redirect that output to the savedata file with the following command:. If a command writes to more than one output, you can independently redirect each one.

Suppose that a command directs its standard output to file descriptor 1, directs its standard error output to file descriptor 2, and builds a data file on file descriptor 9. The following command line redirects each of these outputs to a different file:. The lines between the first eofstring and the second are frequently referred to as an inline input , or here , document.

The shell creates a temporary file containing the here document and performs variable and command substitution on the contents before passing the file to the command.

It performs pattern matching on file names that are part of command lines in command substitutions.