edit first line of long file

Blair P. Houghton bhoughto at cmdnfs.intel.com
Tue Oct 23 10:41:32 AEST 1990


In article <27338 at shamash.cdc.com> ddh at dash@udev.cdc.com (Dan Horsfall) writes:
>Plan A: pass the whole file thru sed, qualifing the search string
>as "1s/.../.../"; sed will look at each line of the file.

sed is the way.  it's not that much slower than cat (0.9
seconds cpu vs. 0.0, but the perceived time was about a
second either way and computed to 0:00).  Anything else
would involve multiple exec's and pipes and several context
switches for each character of data, and then you get
process and I/O collisions.  I'll predict nothing (except
perhaps awk or certainly perl or C) would be faster than
the sed line, and by posting to the net you've just cost
yourself and the world more time, bytes, and money than any
of these choices could possibly be worth.

				--Blair
				  "There are perspectives to
				   consider when the software
				   warns you it's about to spend
				   a lot of net.dough."



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