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| -rw-r--r-- | src/tools/sed.md | 24 |
1 files changed, 24 insertions, 0 deletions
diff --git a/src/tools/sed.md b/src/tools/sed.md index 1bd8185..5b5f741 100644 --- a/src/tools/sed.md +++ b/src/tools/sed.md @@ -6,6 +6,8 @@ sed [opts] [script] [file] -i edit file in place -i.bk edit file in place and create backup file (with .bk suffix, can be specified differently) + --follow-symlinks + follow symlinks when editing in place -e SCRIPT add SCRIPT to commands to be executed (can be specified multiple times) -f FILE add content of FILE to command to be executed @@ -60,6 +62,12 @@ echo -e 'aa\nbb' | sed '2aABC' echo -e 'aa\nbb' | sed '2cABC' # aa # ABC + +# Insert before pattern match. +echo -e 'aa\nbb' | sed '/bb/i 123' +# aa +# 123 +# bb ``` ### Substitute lines @@ -76,3 +84,19 @@ echo -e 'foo\nbar' | sed -e 's/foo/FOO/' -e 's/FOO/BAR/' # BAR # bar ``` + +### Edit inplace through symlink +```sh +touch file +ln -s file link +ls -l link +# lrwxrwxrwx 1 johannst johannst 4 Feb 7 23:02 link -> file + +sed -i --follow-symlinks '1iabc' link +ls -l link +# lrwxrwxrwx 1 johannst johannst 4 Feb 7 23:02 link -> file + +sed -i '1iabc' link +ls -l link +# -rw-r--r-- 1 johannst johannst 0 Feb 7 23:02 link +``` |