Delete newlines in a pipe
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Problem statement: Given {cmd} that emits lots of blank lines, delete all
blank lines in a pipe.
The following is a very elegant (and easy to remember!) way to do so:
shell
{cmd} | awk 'NF'From the LLM:
When you use awk ‘NF’, it evaluates to true for lines where NF is greater than zero—that is, lines that are not empty or do not consist solely of whitespace. This makes it a concise way to filter out blank lines.
Other ways with classic tools and regular expressions:
shell
{cmd} | grep -v '^[[:space:]]*$'
{cmd} | sed -e '/^[[:space:]]*$/d'They are just a bit harder to remember.