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0 pointsretrac2y ago0 comments

Worth noting that the Unix shell itself is not a "built-in". The kernel is agnostic about the user interface, which is left entirely to userspace programs to implement. (That was one of Unix's major innovations.)

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pkulak2y ago

/bin/sh is a POSIX requirement though.

rascul2y ago

sh is, but not the location.

> Applications should note that the standard PATH to the shell cannot be assumed to be either /bin/sh or /usr/bin/sh, and should be determined by interrogation of the PATH returned by getconf PATH, ensuring that the returned pathname is an absolute pathname and not a shell built-in.

https://pubs.opengroup.org/onlinepubs/9699919799/utilities/s...

However, in my experience, I don't recall seeing any POSIX or POSIX like system that didn't have /bin/sh.

pkulak2y ago

Oh interesting. I assumed that since even Nix has a hard-coded /bin/sh, it must be required. Probably _essentially_ required.

whimsicalism2y ago

built in to the shell, not the kernel lol

j / k navigate · click thread line to collapse

0 pointsretrac2y ago0 comments

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pkulak2y ago

/bin/sh is a POSIX requirement though.

rascul2y ago

sh is, but not the location.

https://pubs.opengroup.org/onlinepubs/9699919799/utilities/s...

However, in my experience, I don't recall seeing any POSIX or POSIX like system that didn't have /bin/sh.

pkulak2y ago

Oh interesting. I assumed that since even Nix has a hard-coded /bin/sh, it must be required. Probably _essentially_ required.

whimsicalism2y ago

built in to the shell, not the kernel lol

j / k navigate · click thread line to collapse