What is the difference between sys.stdout.write
and print
in Python? Are there situations where using sys.stdout.write()
is preferable to using print
to stdout? (For example, in terms of better performance or code clarity)
I’ve worked quite a bit with Python, and one thing I’ve noticed is that sys.stdout.write
can be slightly more performant than print
in some scenarios. This is because print
in Python actually calls sys.stdout.write
under the hood but adds an automatic newline at the end of every call. So, if you’re working with a large volume of output or need tighter control over performance, sys.stdout.write
is often a better choice. For example, when you’re streaming data or printing in loops, removing the automatic newline in Python print to stdout operations can make your output handling leaner and more efficient.
I completely agree with Priyanka’s point about performance, and I’d like to add that sys.stdout.write
also shines when you need fine-grained control over how your output looks. Since it doesn’t add a newline unless you specify it, you can craft outputs that are more precise—like printing progress updates on the same line or generating compact logs. On the other hand, print
offers convenience with built-in features like automatically adding spaces between multiple arguments or easily customizing the end character. This makes print
the go-to for many typical scenarios involving Python print to stdout, but for advanced formatting, sys.stdout.write
wins out.
Building on what Priyanka and Miro said, I’d say sys.stdout.write
becomes invaluable when dealing with intricate formatting or working with file-like objects. For instance, while print
handles automatic formatting and interprets special characters (like \n
), this can sometimes lead to unintended results. In contrast, sys.stdout.write
treats the output as raw text, which is perfect for managing complex streams or writing structured logs where you don’t want Python print to stdout operations to modify your data. It’s especially handy in cases like redirecting output to files or pipes where you need complete control over how your data is written.