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Full Discussion: Sed: deleting last line prevents '$' address from working in the multi-script invocation
Top Forums Shell Programming and Scripting Sed: deleting last line prevents '$' address from working in the multi-script invocation Post 302957520 by msz59 on Monday 12th of October 2015 11:56:52 AM
Old 10-12-2015
Sed: deleting last line prevents '$' address from working in the multi-script invocation
It looks like if matching and deleting the last line confuses 'sed' so it does not recognize '$' address. Consider:

Code:
sed -e '/^3/d' -e '$ a text'

supposed to delete a line starting with '3' and then append 'text' after the last line of input. But, if it is the last line of input which starts with '3' it gets deleted but nothing is appended.

Code:
echo "1\n2\n3" | sed -e '/^3/d' -e '$ a text'
1
2

versus
Code:
echo "1\n2\n3\n4" | sed -e '/^3/d' -e '$ a text'
1
2
4
text

Is this the expected behavior or a bug?

regards, Michal.
Last edited by Don Cragun; 10-12-2015 at 03:31 PM.. Reason: Add CODE tags.
 

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bup-margin

bup-margin(1)						      General Commands Manual						     bup-margin(1)

NAME

       bup-margin - figure out your deduplication safety margin

SYNOPSIS

       bup margin [options...]

DESCRIPTION

       bup margin  iterates  through  all  objects  in	your  bup repository, calculating the largest number of prefix bits shared between any two
       entries.  This number, n, identifies the longest subset of SHA-1 you could use and still encounter a collision between your object ids.

       For example, one system that was tested had a collection of 11 million objects (70 GB), and bup margin returned 45.  That  means  a  46-bit
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AUTHORS

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Bup unknown-															     bup-margin(1)
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