std: Add a note about the print! macro and output buffering #23826
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r? @huonw (rust_highfive has picked a reviewer for you, use r? to override) |
| @@ -64,6 +64,9 @@ macro_rules! panic { | |||
| /// | |||
| /// Equivalent to the `println!` macro except that a newline is not printed at | |||
| /// the end of the message. | |||
| /// | |||
| /// Note that because stdout is by default unbuffered on unix systems, this may | |||
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Shouldn't this be buffered instead?
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Err, yeah. Thanks for the catch!
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It would be helpful if this had a reference to the |
| @@ -64,6 +64,9 @@ macro_rules! panic { | |||
| /// | |||
| /// Equivalent to the `println!` macro except that a newline is not printed at | |||
| /// the end of the message. | |||
| /// | |||
| /// Note that because stdout is by default buffered on unix systems, this may | |||
| /// result in output not being emitted until stdout is flushed. | |||
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I think this may want to be rephrased to not mention unix and also mention "line buffering" somewhere, perhaps:
Note that stdout is frequently line-buffered by default so it may be necessary to use
io::stdout().flush()to ensure the output is emitted immediately.
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Totally reasonable, is there markup to make it actually linkify io::stdout ? (Will it do this by default? That would be amazing)
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Unfortunately, no, there is no default auto-linking, but you can always do it manually via [foo](../bar/baz.html)
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I updated the doc comment. Including the link inline made it no longer possible to just copy the invocation out of the comment, which I felt outweighed the benefit. |
| @@ -64,6 +64,9 @@ macro_rules! panic { | |||
| /// | |||
| /// Equivalent to the `println!` macro except that a newline is not printed at | |||
| /// the end of the message. | |||
| /// | |||
| /// Note that stdout is frequently line-buffered by default so it may be necessary to use | |||
| /// io::stdout().flush() to ensure the output is emitted immediately. | |||
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Can you match the surrounding style and wrap this to 80-characters as well? Also, can you put io::stdout().flush() in backticks as well?
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Done, apologies somehow tw got screwed up in my editor.
cc #23818