sed

问题 I have the following test file AAA BBB CCC Using the following sed I can comment out the BBB line. # sed -e '/BBB/s/^/#/g' -i file I'd like to only comment out the line if it does not already has a # at the begining. # sed -e '/^#/! /BBB/s/^/#/g' file sed: -e expression #1, char 7: unknown command: `/' Any ideas how I can achieve this? 回答1: Assuming you don't have any lines with multiple # s this would work: sed -e '/BBB/ s/^#*/#/' -i file Note: you don't need /g since you are doing at most

问题 I have the following test file AAA BBB CCC Using the following sed I can comment out the BBB line. # sed -e '/BBB/s/^/#/g' -i file I'd like to only comment out the line if it does not already has a # at the begining. # sed -e '/^#/! /BBB/s/^/#/g' file sed: -e expression #1, char 7: unknown command: `/' Any ideas how I can achieve this? 回答1: Assuming you don't have any lines with multiple # s this would work: sed -e '/BBB/ s/^#*/#/' -i file Note: you don't need /g since you are doing at most

来源： https://stackoverflow.com/questions/64358324/use-date-command-to-reformat-date-within-sed-command-in-bash-script

来源： https://stackoverflow.com/questions/64358324/use-date-command-to-reformat-date-within-sed-command-in-bash-script

来源： https://stackoverflow.com/questions/64358324/use-date-command-to-reformat-date-within-sed-command-in-bash-script

来源： https://stackoverflow.com/questions/64613168/linux-centos-sed-command-with-regex-issues

来源： https://stackoverflow.com/questions/55607925/extract-json-value-with-sed

来源： https://stackoverflow.com/questions/28795479/awk-sed-script-to-convert-a-file-from-camelcase-to-underscores

来源： https://stackoverflow.com/questions/14131020/sed-regexp-looking-for-either-whitespace-or-end-of-line

来源： https://stackoverflow.com/questions/37711062/using-sed-to-delete-lines-containing-slashes