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| author |   Ulrich Müller <ulm@gentoo.org> | 2020-01-08 10:24:41 +0100 |
|---|---|---|
| committer | Ulrich Müller <ulm@gentoo.org> | 2020-01-09 09:31:55 +0100 |
| commit | c2e9f75dbf89db8e19615dc0b15b05f4d5698584 (patch) | |
| tree | aa7bb64f7a3de431b7cf0b8e2bb62a7dac21d270 /tools-reference/head-and-tail | |
| parent | tools-reference/head-and-tail: Line counting in tail starts at 1. (diff) | |
| download | devmanual-c2e9f75dbf89db8e19615dc0b15b05f4d5698584.tar.gz devmanual-c2e9f75dbf89db8e19615dc0b15b05f4d5698584.tar.bz2 devmanual-c2e9f75dbf89db8e19615dc0b15b05f4d5698584.zip | |
tools-reference/head-and-tail: Add another example for tail.
The bad example is taken from the script referenced in bug 536654.
Signed-off-by: Ulrich Müller <ulm@gentoo.org>
Diffstat (limited to 'tools-reference/head-and-tail')
| -rw-r--r-- | tools-reference/head-and-tail/text.xml | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/tools-reference/head-and-tail/text.xml b/tools-reference/head-and-tail/text.xml index e2b7553..06f17de 100644 --- a/tools-reference/head-and-tail/text.xml +++ b/tools-reference/head-and-tail/text.xml @@ -36,6 +36,14 @@ To specify "the last five lines", use <c>tail -n5</c>. To specify "all but the first five lines", use <c>tail -n+6</c>. </p> +<codesample lang="ebuild"> +# bad: drop first five lines, clumsily computing line count +tail -n $(($(wc -l in.txt | awk '{print $1}') - 5)) in.txt > out.txt + +# good: let tail count lines from the beginning of the file +tail -n +6 in.txt > out.txt +</codesample> + <warning> <c>head/tail -5</c> syntax is deprecated and not POSIX compliant. </warning> |