Facebook
Digg
StumbleUpon
del.icio.usThese are all little things I type on the command line to do various tasks. They don't have much in the way of error handling, but they sure are useful. They are all for Bourne-compatible shells on FreeBSD, unless specified otherwise. These can also be used to do similar tasks; they aren't all one-trick ponies.
Delete files from a list in list.txt.
perl -nle unlink < list.txt
Find corrupt JPEG images in the current directory.
find . -iname \*.jp\* -exec jpeginfo -cq {} \; | grep -v '[OK]'
Ping the default route, useful for testing internet connectivity.
ping `netstat -rn | awk '/default/ {print $2}'`
Run COMMAND every N seconds.
while sleep N ; do COMMAND ; done
Run COMMAND, and suppress all of its output, good or bad.
COMMAND > /dev/null 2>&1
Watch a text file be appended.
tail -f file
Grab the decription of a sysctl
sysctl -d kern.ipc.nmbclusters
Check the interrupt count and interrupt rate of all devices.
vmstat -i
Create a whole bunch of symlinks all at once.
for S in cars bikes planes
do
ln -s /home/images/${S} /home/craig/${S}-images
done
Get a nice little table of contents for FreeBSD manpages.
for M in `jot 9 1` ; do (man $M intro | head -1) 2>/dev/null ; done
Get the size of the current working directory in bytes. Useful for further scripting.
find . -type f | perl -nle '$size += -s; END {print $size}'
List installed packages that are out-of-date, have a corrupted list, or are otherwise not perfect, and provide a line count at the end.
pkg_version -vL= | tee /dev/stderr | wc -l
Delete all ports, and then install them again, without handling any errors or avoiding repetition from building dependencies more than once.
cd /tmp
pkg_info -aoq > pkgtmp
pkg_delete -fa
for F in `cat pkgtmp`
do
cd /usr/ports/${F}
make install clean
done
