2012年10月19日 · Great works a treat. I guess _ in there means to look for numbers only after the underscore? In this instance I can always expect an underscore so this will work.

2023年8月2日 · Syntax is similar to sed, but certainly not exactly the same. Even if you don't have a -i supporting sed, you can easily write a script to do the work for you. Instead of sed -i 's/foo/bar/g' file, you could do inline file sed 's/foo/bar/g'. Such a …

2015年6月3日 · In your example sed 's/foo/bar/' and sed -e 's/foo/bar/' are equivalent. In both cases s/foo/bar/ is the script that is executed by sed. The second option is more explicit, but that is probably not the reason that you often see -e used. The reason for that is that -e makes it possible to use more than one script with the same invocation of sed ...

The single quotes around the sed body will prevent the shell from substituting any variables, so the $ on the left-hand side is escaped only to prevent its special regular expression meaning. – glenn jackman

2013年2月11日 · sed uses basic regular expressions by default, enabling use of extended regular expressions is implementation dependent, e.g. with BSD sed you use the -E switch, GNU sed has it documented as -r, but -E works as well.

2013年8月30日 · sed 's/"p"/0/g' file.txt > file.txt Unfortunately because of the nature of redirects the above will simply produce a blank file. Instead a temp file must be created for the output which later overwrites the original file something like this:

For sed -i 's/old/new' *, the expansion of * must ALL be passed as an arglist to sed, and I'm fairly sure this has to happen before the sed process can even be started. Using the for loop, the full arglist (the expansion of *) never gets passed as a command, only stored in the shell memory and iterated through. I don't have any reference for ...

2017年5月23日 · @AbdullahJibaly The role of /g is unrelated to anything in the back reference. Without /g, sed will only substitute the first occurrence of the regex on each line; with /g you are saying, "if that succeeded, proceed from that point in the input string and replace the next one, too; repeat until you cannot find any more matches."

@tripleee While I'm certain that this would be a duplicate of numerous other questions, the one that you've pointed to isn't the best one since it doesn't contain slashes in the variable.

You need to quote \[.*^$/ in the regular expression part of the s command and \&/ in the replacement part, plus newlines.