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# 1  
Old 05-05-2005
/dev/null
Hi ,

I am importing some table from /dev/null i dont understand what is /dev/null

Sorry i am new to UNIX

sam71
# 2  
Old 05-05-2005
Importing a table from /dev/null? /dev/null is the null device (does what it says on the tin....). Importing from /dev/null would (without seeing whatever code it is that you're referring to) probably clear the table of all data. Same applies when catting /dev/null to a file....

cat /dev/null > somefile

would truncate to 0 bytes

This in itself is a bit of a UUOC as >somefile would do the same thing.

Please post the piece of code you're referring to if you'd like an answer that's a little less vague.

Cheers
ZB
# 3  
Old 05-05-2005
/dev/null
Hi,
following command i use with connected to database from unix box,

db2 "import from /dev/null of del modified by chardel< coldel| replace into table name"

this is the code and it refresh the data from table when i run this code.

thanks

sam71
# 4  
Old 05-05-2005
Code:
NULL(4)             Linux Programmer's Manual             NULL(4)

NAME
       null, zero - data sink

DESCRIPTION
       Data written on a null or zero special file is discarded.

       Reads  from the null special file always return end of file, whereas reads
       from zero always return \0 characters.

       null and zero are typically created by:

              mknod -m 666 /dev/null c 1 3
              mknod -m 666 /dev/zero c 1 5
              chown root:mem /dev/null /dev/zero

NOTES
       If these devices are not writable and readable for all  users,  many  pro-
       grams will act strange.

FILES
       /dev/null
       /dev/zero

SEE ALSO
       chown(1), mknod(1)

Linux                       1992-11-21                    NULL(4)

 
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