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awk - How do I make these sed commands into a oneliner


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The pipe character (|) is interpreted by shell and it is used to glue together commands (like cat | sed in your case). sed knows nothing about this and that's the first issue that I see in the example.

So, you can chain many sed commands into one like this:

cat ... | sed 's/aa/bb/' | sed 's/cc/dd/' >file

Another approach is to execute sed only once and pass all sed commands separated by a semicolon:

cat ... | sed 's/aa/bb/;s/cc/dd/' >file

Alternatively, you can provide them with -e option:

cat ... | sed -e 's/aa/bb/' -e 's/cc/dd/' >file

Note also, that when you used many sed commands, you also passed -i option that tells sed to modify a file in-place. But when you use pipe and redirect stdout to a file, you shouldn't pass this option because sed can't modify a file because there is no file, all data comes from stdin.


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