Thank you, I didn't know about the `cat -` trick to read from stdin (works the s... | Hacker News

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zackmorris on March 21, 2018 | parent | context | favorite | on: Blocklist Facebook domains

Thank you, I didn't know about the `cat -` trick to read from stdin (works the same as `echo hi | cat /dev/stdin`). Even after all this time, I still learn something new every day.

wwalexander on March 23, 2018 [–]

    echo hi | cat -

is also equivalent to

    echo hi | cat

You only need the - if you are concatenating other files with stdin [1]. Incidentally, any use of

    echo x | y

can be replaced (at least in Bash) with

    y <<< "x"

This is called a "here string" [2].

[1] https://www.freebsd.org/cgi/man.cgi?query=cat&manpath=FreeBS...

[2] http://tldp.org/LDP/abs/html/x17837.html

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