Created attachment 488897 [details]
Patch for tailf in util-linux(-ng)

Description of problem:
'tailf' does not accept a zero line count (i.e., '-n 0') -- useful for
seeing only new arrivals.
'tail -f' does accept it; the two should be compatible.

Version-Release number of selected component (if applicable):
util-linux-ng-2.18-4.8.fc14.i686
util-linux-2.19-1.fc15.i686

How reproducible:
100%

Steps to Reproduce:
1. tailf -n 0 /var/log/messages

Actual results:
tailf: invalid number of lines

Expected results:
Nothing printed (until new entries to /var/log/messages are made).

Additional info:
A patch is attached (use with '-p1' in spec file).  Changes are simple:
    Two instances of "<=" changed to "<" (in argv processing).
    Call tailf() only if lines > 0 .

BTW, unlike 'tail', 'tailf' insists on a space after the '-n' (i.e., it
must be '-n 0', not '-n0').