alt Hacker NewsThe beauty of cat is that streams are the universal interface.
Program A might accept a file as the last positional arg. Program B might accept it as a named arg, where the name/flag could be anything from --input or -f or --file etc.
But a program will read from STDIN, which all good unix programs do, then piping cat into it works every time. I can write the cat foo.txt part before I even know what command I'm piping it into.
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Yeah, I read TFA, and my eyes were rolling the whole time. Some people really have a bee in their bonnet that "cat" is named that way because it was originally for concatenating files. Nobody fucking cares. It's the standard way for writing a file to standard out, and the general pattern of "cat file.txt | somecommand | othercommand | anothercommand" is so useful because it follows the pipeline pattern so well - read from standard in, write to standard out - that is the cornerstone of Unix shell commands IMO.
"Oh no, it spawns another process!!" Again, nobody cares.
This. Sometimes I want to see what I'm looking at and then (using that dump as a reference) follow up with a corresponding filter (| jq .key, or | tail -n 30). Sure, I could use less, but then I context switch on exit; no support from the scrollback buffer.
I've probably lost 10ms * 1E5 of my life from the extra PID. But, probably would lose more in the context switch.