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commit: c2e9f75dbf89db8e19615dc0b15b05f4d5698584 |
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Author: Ulrich Müller <ulm <AT> gentoo <DOT> org> |
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AuthorDate: Wed Jan 8 09:24:41 2020 +0000 |
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Commit: Ulrich Müller <ulm <AT> gentoo <DOT> org> |
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CommitDate: Thu Jan 9 08:31:55 2020 +0000 |
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URL: https://gitweb.gentoo.org/proj/devmanual.git/commit/?id=c2e9f75d |
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|
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tools-reference/head-and-tail: Add another example for tail. |
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|
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The bad example is taken from the script referenced in bug 536654. |
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|
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Signed-off-by: Ulrich Müller <ulm <AT> gentoo.org> |
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|
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tools-reference/head-and-tail/text.xml | 8 ++++++++ |
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1 file changed, 8 insertions(+) |
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|
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diff --git a/tools-reference/head-and-tail/text.xml b/tools-reference/head-and-tail/text.xml |
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index e2b7553..06f17de 100644 |
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--- a/tools-reference/head-and-tail/text.xml |
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+++ b/tools-reference/head-and-tail/text.xml |
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@@ -36,6 +36,14 @@ To specify "the last five lines", use <c>tail -n5</c>. To specify "all |
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but the first five lines", use <c>tail -n+6</c>. |
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</p> |
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|
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+<codesample lang="ebuild"> |
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+# bad: drop first five lines, clumsily computing line count |
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+tail -n $(($(wc -l in.txt | awk '{print $1}') - 5)) in.txt > out.txt |
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+ |
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+# good: let tail count lines from the beginning of the file |
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+tail -n +6 in.txt > out.txt |
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+</codesample> |
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+ |
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<warning> |
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<c>head/tail -5</c> syntax is deprecated and not POSIX compliant. |
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</warning> |
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