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How to use sed to convert all caps to lowercase?
That means that the first sentence would then read, ‘i have a textfile in which some words are printed in all caps.’ Or, sed on GNU (but not BSD or Mac as they don’t support \\L or \\U ): If you have GNU extensions, you can use sed’s \\L (lower entire match, or until \\L [lower] or \\E [end – toggle casing off] is reached), like so:
Is there a way to convert all letters from uppercase to lowercase?
That is to change the cases of all the letters. It has to be done with a sed replacement somehow. or a shorter way with GNU sed, working with any character for which a lowercase<->uppercase conversion exists in your locale:
Is it possible to transliterate all letters in SED?
POSIXly, that can’t be done with sed except by providing the complete set of letters you want to transliterate as @cuonglm has shown. It could be done with tr though, and that’s what tr is for (transliterate):
What do characters do I need to escape when using SED?
\\ followed by a digit has a special meaning. \\ followed by a letter has a special meaning (special characters) in some implementations, and \\ followed by some other character means \\c or c depending on the implementation. With single quotes around the argument ( sed ‘s/…/…/’ ), use ‘\\” to put a single quote in the replacement text.
Are there any special characters in GNU sed?
However, while GNU sed does allow for the functionality of some special characters, they are still not actually POSIX-compliant. Additionally, the only real difference between basic and extended regular expression (ERE), within GNU sed, is the behavior of the following special characters:
Are there any special characters in BSD sed?
While this may be the case, some special characters have limited or no support at all on BSD sed, such as ‘|’, ‘?’, and ‘+’, as it more closely adheres to the POSIX syntax standards. The inclusion of those characters, in a fashion similar to that of GNU sed, will often result in issues with portability and functionality of scripts utilizing sed.
When to use ^ upcase-first in Perl?
The ^ upcase-first operator only works at the beginning of a variable (or array element). And there doesn’t seem to be any substring expansion that gives you what perl would call an lvalue (that you can assign to / modify).
When to use E at the end of a substitution in Bash?
The substitution replaces the first instance of _ and the character following it with themselves ( $& is whatever was matched) upper cased ( uc () ), The e at the end of the substitution operator ( s///e) is needed in order to evaluate expressions.
How to upcase a string in Bash 4.x?
Pure Bash 4.x, using a regex to pick out the part you want to upcase, and the ^^ upcase operator on that part. Tacking on the front and back (matched by .*) to re-create the whole string:
How to number all lines in a SED file?
Output file # should contain no more than one blank line between lines of text. sed ‘/^$/d;G’ # triple space a file sed ‘G;G’ # undo double-spacing (assumes even-numbered lines are always blank) sed ‘n;d’ NUMBERING: # number each line of a file (simple left alignment).
Where are the trailing spaces in SED method 1?
In method 1, # spaces at the beginning of the line are significant, and trailing # spaces are appended at the end of the line.
What kind of files can be passed to SED?
Files passed to # sed must be passed in the proper order. Version 1 can be entered # from the command line; version 2 can be made into an executable # Unix shell script.