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Comment by heinrich5991 | Hacker News Reader

This only helps if the program that pipes into less doesn't do terminal detection to decide that it doesn't want to output ANSI color escapes into a pipe (to less).

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You may sometimes be able to work around this by using `expect` which creates a pseudoterminal attached to the program's stdout instead of a pipe. For example, say the program you want to run is `ls --color=auto`. This produces color when stdout is a terminal but no color when stdout is a pipe. If we just did:

    ls --color=auto | less -R

we'd see no color. Instead we can run ls under expect:

    expect -c "spawn -noecho ls --color=auto; expect" | less -R

and color abounds.

There may be an easier way to accomplish this. If anybody has ideas, chime in.

This partially works for me with "cargo test"; it also seems to print a control character ('^O') after every colored string, as well as at very beginning of the output. Additionally, after a certain amount of output (maybe 1.5 times my terminal height), it prints an ellipsis and stops printing anything new.

Thanks a bunch for pointing me towards `expect`, though! I hadn't used it before, and I'll definitely do some experimenting with it to see if I can get my desired output with it.

cargo build --color always | less -R should work with recent cargo, alternativly `cargo rustc --color always -- --color always 2>&1 | less -R` works as well.

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