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A comment on Mkfile(8) is severely syscall limited on OS X. Parent comment

Re:Mkfile(8) is severely syscall limited on OS X by danieldk on Sunday February 12, 2017 @07:59AM (#13628131)
Interesting... You never dd data to a USB3 disk or SSD? The default buffer size for dd on OS X is also 512 bytes. I've been using `bs=1m` on OS X for ages.
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Re:Mkfile(8) is severely syscall limited on OS X by sz4kerto on Sunday February 12, 2017 @08:06AM (#13628151)
Why are you using dd for USB disks?
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Re:Mkfile(8) is severely syscall limited on OS X by danieldk on Sunday February 12, 2017 @08:07AM (#13628156)
Writing bootable installation images?
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Re:Mkfile(8) is severely syscall limited on OS X by sz4kerto on Sunday February 12, 2017 @01:36PM (#13629749)
You should use cp, that's just better for this task.

"dd is not a disk writing tool" http://www.vidarholen.net/contents/blog/?p=479

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Re:Mkfile(8) is severely syscall limited on OS X by chungy on Sunday February 12, 2017 @10:27AM (#13628750)
You could use cp.
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Re:Mkfile(8) is severely syscall limited on OS X by jsjohnst on Sunday February 12, 2017 @11:39AM (#13629088)
cp is designed to copy data across file systems.

dd is designed to copy raw block data across devices.

Sure, you can abuse both for either purpose, but seems rather misguided to call it out explicitly. What did you intend to gain by doing it?

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Re:Mkfile(8) is severely syscall limited on OS X by sz4kerto on Sunday February 12, 2017 @01:38PM (#13629759)
You don't know what cp is for. cp is exactly for copying data from a file to another file -- and under Unix, devices are represented as files. Using cp for writing disk ISOs to an USB drive is proper use, not abuse.

dd is for transform-and-copy, so you're abusing dd when writing disk ISOs. The fact that most of the Internet is wrong doesn't make you any less wrong.

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Re:Mkfile(8) is severely syscall limited on OS X by chungy on Sunday February 12, 2017 @12:39PM (#13629433)
cp is designed to copy data from one file to another. Block devices are represented as files, and cp won't be speed limited by block size.

dd is also designed to copy data from one file to another, in blocks, with optional conversion of the data (eg, from EBCDIC to ASCII), and with optional offsets/limits to copy regions of a file.

dd is not designed to copy raw block data, it is merely a different file copy tool.

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Re:Mkfile(8) is severely syscall limited on OS X by feld on Sunday February 12, 2017 @11:21AM (#13628997)
Explain?
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