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Comment by awelxtr | Hacker News Reader

I use it constantly. My company's products are flashed using an sd card and to create it I dd into and from the sd card several times a week

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I feel that dd is never the correct tool to write to SD cards. At least cp can figure out the block size itself. Or the more elaborated bmaptool can even skip empty blocks which are often found in disk images.

> Or the more elaborated bmaptool can even skip empty blocks which are often found in disk images.

  dd conv=sparse

> At least cp can figure out the block size itself.

Why does it matter? Use `bs=$((4 * 1024 * 1024))`. It'll work perfectly for any imaginable block size.

My issue with dd is that it's possible to write corrupted data with some weird flags which I did once. Something with conv=sync I believe which does unexpected things. But if you're not trying to be too smart, dd works fine.

Reminds me of this: https://www.vidarholen.net/contents/blog/?p=479

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