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Old 08-27-2017, 08:12 PM   #1
GeneCode
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Understanding detected devices?


Hi all.

I am working with barebox Linux right now. I am not sure why some SD card that I plug in, shows as 2 devices:

/dev/disk0.0
/dev/disk0

but another SD card I have only detected as 1 device:

/dev/disk0

I guess it is something to do with partition? Or something? I'd like to know how to get a consistent ref name for a device because I have a script to automount it to a directory.

Thank you
 
Old 08-27-2017, 10:14 PM   #2
GeneCode
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Ok not sure why, but after I reformated the SD card, both now has the same devices.

/dev/disk0.0
/dev/disk0

Anyway I still want to know why there are 2 devices for a single card.
 
Old 08-28-2017, 12:10 AM   #3
jsbjsb001
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Quote:
Originally Posted by GeneCode View Post
Hi all.

I am working with barebox Linux right now. I am not sure why some SD card that I plug in, shows as 2 devices:

/dev/disk0.0
/dev/disk0

but another SD card I have only detected as 1 device:

/dev/disk0

I guess it is something to do with partition? Or something? I'd like to know how to get a consistent ref name for a device because I have a script to automount it to a directory.

Thank you
If I'm understanding your question correctly, the first device node represents the device itself, where as the 0 (or 1, etc) represents the partitions on said device/media (SD card, USB, etc).

For example, if I had a device with 2 partitions on it, and it's got the device node /dev/sda the sda1 would be the first partition on said device/media, with sda2 being the second partition.

The device node given to a device is (to my understanding anyway) decided by the order in which storage devices are "seen" by the kernel.

Hope this helps.

Last edited by jsbjsb001; 08-28-2017 at 12:11 AM.
 
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Old 08-28-2017, 12:13 AM   #4
ondoho
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exactly, partitioning.

Quote:
Originally Posted by GeneCode View Post
/dev/disk0.0
/dev/disk0
/dev/disk0.0 is the first partition
/dev/disk0 is the card itself

there might be even more partitions...
 
1 members found this post helpful.
  


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