Shred
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<yambe:breadcrumb>Security_tools|Security tools</yambe:breadcrumb>
shred
Writing zeros to a file
If there is a need to write all zeros to a file then one can use
shred -n 1 -z <file-name>
Note that 'dd if=/dev/zero of=<file>' wont work as it wont end. So dd would have to be limited using bs, count, etc mechanisms.