Why is a parameter in the POSIX find command added with a single hyphen for multi-character parameter names, while most other programs use single hyphen to indicate multiple single-character flags, and double-hyphens to indicate single parameter names with multiple characters?
I’ve read several question about double dash:
The yash shell has a printf built-in, according to its manual.
I don’t think the shell/utilities in historical Unix nor in something as “recent” as 4.4BSD supported using a double-dash(or two consecutive hyphens) as an end of options delimiter. With FreeBSD, you can see for instance a note introduced in the rm manpages with the 2.2.1 release(1997). But this is just the documentation for one command.
I am trying out shellcheck.
I’m trying to write all of my sh startup/env scripts to work with as much DRY and as much: “works on every *nix I clone it to”, as possible. This means making sure that if I try to run code that’s not there, that the code fails gracefully. To that end I need to be able to test if programs exist. I know how to test if a file exists, but I’m not sure how to test to see if an application is executable within the path. I’d rather use the $PATH, as some of these need to work on arch, ubuntu, and centos. Some might be installed in my homedir, on systems where I don’t have root, others might not be installed, and others yet my be installed in system paths.
Can someone explain to me how umask affects the default mask of newly created files if ACLs are activated? Is there some documentation about this?
When I want to ask for a password in a bash script, I do that :