02-03-2017
Quote:
Originally Posted by
Eggsy
Thanks for your answer. Would you mind helping me to understand how exactly those statements work then.
I'm glad to help, but: instead of delivering ready made answers, I prefer to make you cogitate and find the answers yourself.
Quote:
Is my assumption that "grep s>/dev/null" and "grep r>/dev/null" check whether or not a filename contains an S and an R correct?
Partly. Why should
grep s try to match an
S ? And, recheck your conclusions (what does and when applies the
|| ?).
Quote:
So looking over it again, for 2. would this mean it's invoked 15 times too, because it checks every single file.
Correct!
Quote:
And as for 3. could it be 7 times, since you only reach the "grep r>/dev/null" part when it found an S in the name (since there are only 7 files with an S)?
Count again...
---------- Post updated at 09:10 AM ---------- Previous update was at 09:02 AM ----------
Quote:
a) I believe the filenames were actually all lower case. (As a german, we capitalize names, so that was my mistake when I wrote this down)
So...?
Quote:
b) || means we only reach the right side, when the left side is true, iirc. So once it found a filename with an "s", it checks for an "r"?
Please double check the
|| operator in shell scripts.
Quote:
1. We have 15 items. So it goes through the list of files until every single one was checked?
And how is end-of-file detected?
Quote:
2. Also 15 times, since it checks every single item for an "s"?
Drop the "also"; then, yes.
Quote:
3. 7 times, since we only reach the second part, when we found an item with an "s"
see answer to b)
Quote:
4. 3 times, since we only have reach that part, when we found an item with an "s" and an "r"
see answer to b)
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