We are stuck with egrep and fgrep (unless you like beating people)

Post by saalweachter » Thu, Oct 13, 2022, 4:44 PM UTC

masklinn wrote: post #195

saalweachter wrote: post #159

Earlier quoted context omitted.

At a guess, it isn't actually the symlinks, it's the argument parsing they're trying to simplify. Old programs have stupidly complex argument parsing. If you can pass your arguments as "cmd foo bar path", "cmd -f bar path", "cmd -fbar path", "cmd path --foo=bar" or "fcmd bar path" and "cmdf path bar", it can be really convenient for users who can structure their commands in the way that makes the most sense for them.…

> At a guess, it isn't actually the symlinks, it's the argument parsing they're trying to simplify. There’s no parsing. GNU’s egrep and fgrep are trivial shell scripts: #!/bin/sh exec grep -E "$@"

Post by paulmd » Thu, Oct 13, 2022, 4:48 PM UTC

barrkel wrote: post #114

radford-neal wrote: post #107

I use fgrep all the time. Why should I spend time converting scripts, and retraining my fingers, and forever after taking longer to type grep -F? This is a breaking change that has no upside, only downside. It is idiocy. Just to elaborate, there must be many thousands (hundreds of thousands? millions?) of shell scripts out there that use fgrep. For no reason at all (whatever maintenance burden fgrep represents must b…

There's a certain type of person who gets pleasure from following rules exactly, particularly when other people don't follow those rules. A kind of smug moral superiority. If they get into a position of power, they can make life worse for other people, without much regard for the actual cost of breaking such rules. Removing egrep and fgrep is desperately petty stuff.

Post by henearkr » Thu, Oct 13, 2022, 4:54 PM UTC

henearkr wrote: post #126

emptyparadise wrote: post #20

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#!/bin/sh exec grep -E "$@"

The current contents (not joking): (this is why the situation is crazy) #!/bin/sh cmd=${0##\*/} echo "$cmd: warning: $cmd is obsolescent; using grep -E" >&2 exec grep -E "$@"

Post by Taywee » Thu, Oct 13, 2022, 4:56 PM UTC

hinkley wrote: post #235

ratmice wrote: post #177

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The gnu coding standards has this to say: https://www.gnu.org/prep/standards/standards.html#index-beha... Please don’t make the behavior of a utility depend on the name used to invoke it. It is useful sometimes to make a link to a utility with a different name, and that should not change what it does. The next section provides some reasoning: Providing valid information in argv[0] is a convention, not guaranteed. Wel…

Different behavior based on argv[0] was first brought to my attention when I discovered that /bin/sh was a symlink on some Linux systems. Bash has a Bourne shell compatibility mode.

Post by smellf » Thu, Oct 13, 2022, 5:01 PM UTC

mananaysiempre wrote: post #194

pbhjpbhj wrote: post #175

Earlier quoted context omitted.

Aside: What do you mean by "use a symbolic link" (I'm familiar with `ln -s` fwiw) the alias carries the command switch, how do you do that with a link? # example alias egrep='grep -E' ??

Currently, egrep and fgrep are shell scripts (the too-simple version of this idea would be #!/bin/sh exec /usr/bin/grep -E "$@" but that would mess up help messages and probably also needs disaster handling in case exec fails). Another traditional way, however, is to symlink everything to a single binary, which uses argv[0] or getprogname() to see which name the user called it under and acts accordingly. In the extre…

    cat `which egrep`
    #!/bin/sh
    exec grep -E "$@"