[Top][All Lists]
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
bug#7157: df should default to -P if output is not a tty
From: |
Alain Knaff |
Subject: |
bug#7157: df should default to -P if output is not a tty |
Date: |
Mon, 04 Oct 2010 11:44:15 +0200 |
User-agent: |
Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.9.2.9) Gecko/20100907 Fedora/3.1.3-1.fc13 Lightning/1.0b2 Thunderbird/3.1.3 |
Hello,
We just had a case where an overfull disk went unnoticed by logwatch.
The reason turned out to be its long device name (/dev/mapper
/VolGroup00-LogVol00), which caused df to break the line, messing up
the column count. Indeed, logwatch looks for the use% in the fifth
field, but due to this line breaking, the use% for this disk ended up
in the _fourth_ field of the next line instead.
There is an option to prevent this behavior (-P), but apparently the
logwatch authors were not aware of it. Understandably, I might say,
because if their test cases happen to only have disks with short names,
they'll never stumble upon this.
So, in the name of the "principle of least surprise" wouldn't it be
possible to make -P the default if the output is not a tty (and add an
additional flag for those rare cases where this line-breaking behavior
is actually wanted on non-tty's)
Other utilities, such as Debian's dpkg -l, also default to this
behavior (trimming lines to window width if output is a tty, and not
trimming it if output is not a tty). Same thing for ls (column output
on a tty, one file-name per line on non-tty)
The problem was observed on version coreutils-8.4-8.fc13.i686:
# df | cat
Filesystem 1K-blocks Used Available Use% Mounted on
/dev/mapper/VolGroup00-LogVol00
66688656 47463424 15782956 76% /
/dev/cciss/c0d0p1 197546 19124 168223 11% /boot
tmpfs 517468 12 517456 1% /dev/shm
Thanks,
Alain
- bug#7157: df should default to -P if output is not a tty,
Alain Knaff <=