What is BSD sed?

What is BSD sed?

BSD sed : always appends a newline on output, even if the input line doesn’t end in one. GNU sed : preserves the trailing-newline status, i.e., it appends a newline only if the input line ended in one.

Does Macos have sed?

Or, you can install the GNU version of sed in your Mac, called gsed, and use it using the standard Linux syntax. Your Mac does indeed run a BASH shell, but this is more a question of which implementation of sed you are dealing with.

How do I use GNU sed on Mac?

GNU sed on Mac OS X

1. Disable Mac OS X System Integrity Protection (aka rootless).
2. Install Xcode (via Mac App Store)
3. Install Xcode Command Line Tools: xcode-select –install.
4. Untar the sed package you just downloaded.
5. cd into the unpacked GNU sed directory then run: ./configure –prefix=/usr/ –program-suffix=-gnu.

What’s the difference between OS X and BSD sed?

While the BSD sed shipped with OS X seems to need sed -i ” …, the GNU sed Linux distributions usually come with interprets the quotes as empty input file name (instead of the backup extension), and needs sed -i … instead. Is there any command line syntax which works with both flavors, so I can use the same script on both systems?

Why are there no newlines in BSD sed?

(note lack of mentioning of newlines). GNU sed, however, includes newlines in the set of characters to display unambiguously. It does this as an extension to the set of characters that the POSIX standard for sed mentions (which is the set that BSD sed uses). GNU sed behaves this way even if –posix is used on the command line.

What kind of regular expressions does SED use?

By default sed uses POSIX Basic Regular Expressions, which don’t include the | alternation operator. Many versions of sed, including GNU and FreeBSD, support switching into Extended Regular Expressions, which do include | alternation. How you do that varies: GNU sed uses -r, while FreeBSD, NetBSD, OpenBSD, and OS X sed use -E.

Can a SED be listed on a separate line?

Each option can be listed on a separate line, and sed will evaluate each one. It’s a logical equivalent of or. For example, to remove lines that contain a certain code: Here’s a technique that does not make use of any implementation specific options to sed (e.g. -E, -r ).