How do I truncate output in BASH?
For example, if I "du file.name" how do I just get the numeric value and nothing more?
later addition:
all solutions work perfectly. I chose to accept the most enlightning "cut" answer because I prefer the simplest approach in bash files others are supposed to be able to read.
If you know what the delimiters are then cut is your friend
du | cut -f1
Cut defaults to tab delimiters so in this case you are selecting the first field.
You can change delimiters: cut -d ' ' would use a space as a delimiter. (from Tomalak)
You can also select individual character positions or ranges:
ls | cut -c1-2
I'd recommend cut, as others have said. But another alternative that is sometimes useful because it allows any whitespace as separators, is to use awk:
du file.name | awk '{print $1}'
du | cut -f 1
If you just want the number of bytes of a single file, use the -s operator.
SIZE=-s file.name
That gives you a different number than du, but I'm not sure how exactly you're using this.
This has the advantage of not having to run du, and having bash get the size of the file directly.
It's hard to answer questions like this in a vacuum, because we don't know how you're going to use the data. Knowing that might suggest an entirely different answer.
-s operator work? The only one I know of is for the conditional expression to test whether a file exists and is not empty: [[ -s file.name ]] && echo "yes" for example, but that doesn't tell me the actual size.