Unix pipe to null

Find and replace a column that has '' to NULL in a comma delimited using awk or sed. Hi this is my first time posting ever. I'm trying to replace the 59th column in a file where if I encounter '' then I would like to replace it with the word NULL.

Search and replace string only in a particular column in a delimited file. I have file with multiple columns. Column values for a record may be same.

Now i have to replace a column value this can be same for the other columns with new value. Grep for NULL in a pipe delimited file. Please reply 5 Replies. RedHat Commands. OpenSolaris Commands. Linux Commands. SunOS Commands. FreeBSD Commands. Full Man Repository. Advanced Search. If you tend to forget the file descriptor of stdout and stderr , the following command will do just fine. This is an interesting one.

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Student of CSE. Improve this question. Noodles Noodles 2 2 silver badges 9 9 bronze badges. Why do you think it's OK to close fd[1] twice? In the first example, you close the write side of the pipe before you fork the second child, so that child cannot write into the pipe. You fix it by moving the close. What's the question? Ah, I get it. Thank you, I forgot that the second child would have the writing end closed!

You should always test the return count of write. Especially for pipes and sockets, partial write do happen — Basile Starynkevitch.

Add a comment. Active Oldest Votes. Improve this answer. On terminals, this is okay, but when working with pipes, this can cause severe issues. Sign up to join this community. The best answers are voted up and rise to the top. Stack Overflow for Teams — Collaborate and share knowledge with a private group. Create a free Team What is Teams? Learn more. Asked 6 months ago. Active 6 months ago.

Viewed 1k times. Improve this question. Nassim Bentarka Nassim Bentarka 31 5 5 bronze badges. I ran a process with PID