Jot*_*tne 5

为什么不呢 awk

awk '{print $0"\n"}' file
aaaa

bbbb

cccc
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或这个:

awk 1 ORS="\n\n" file
aaaa

bbbb

cccc
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或这个:

awk '$0=$0"\n"' file
aaaa

bbbb

cccc
Run Code Online (Sandbox Code Playgroud)