Re:Useful Unix commands for exploring data
by danielweber on Wednesday August 27, 2014 @01:10PM
(#8233276)
long_running_process > filename.tmp && mv filename.tmp filename
The rename is atomic; anyone opening "filename" will get either the old version, or the new version. (Although it breaks one of my other favorite idioms for monitoring log files, "tail -f filename", because the old inode will never be updated.)
Re:Useful Unix commands for exploring data
by discardorama on Wednesday August 27, 2014 @01:17PM
(#8233321)
> Although it breaks one of my other favorite idioms for monitoring log files, "tail -f filename", because the old inode will never be updated
You should look into the '-F' option of tail; it follows the filename, and not the inode.
you could directly write to uniqMovie.csv in your example. I would do it like below but ONLY once I am certain it is exactly what I want. Usually I just make one clearly named result file per operation without touching the original.
uniq -u movies.csv > /tmp/temp.csv && mv /temp/temp.csv movies.csv
Re:Useful Unix commands for exploring data
by icebraining on Wednesday August 27, 2014 @12:04PM
(#8232842)
$ temp.csv > movie.csv
temp.csv: command not found
uniq -u movies.csv > temp.csv
temp.csv > movie.csv
rm temp.csv