Convert internal rc_getline() calls to getline() calls

[williamh]

getline has been in posix since POSIX.1-2008, so it should be safe for
us to use it instead of using our wrapper function.

[williamh]

I would like to call for some testers to make sure this works before I merge it. Please report back here.

[dwfreed]

getline's behavior does not match rc_getline's in various ways, like whether the newline is included if found (getline: yes, rc_getline: no). You should just make rc_getline a wrapper for getline, so that this can be fixed in one location, instead of having to do it in several.

[williamh]

@dwfreed The whole reason rc_getline was written was because getline wasn't standard when it was needed. Also, the code already uses both rc_getline and getline. I think I would still rather migrate to getline.

[williamh]

@dwfreed I see that rc_getline is only used in librc. If I do a wrapper, I would want it to be private to the library, not available for general use.

[vapier]

the low usage rates implies it's not a big deal to drop even if it slightly simplifies trailing newline semantics. everyone is used to the posix api at this point so it's a bit of a lost battle.

technically we'd need to keep the symbol just to not break abi.

[williamh]

@vapier I could use some insight here. Is it ok in this case because of the low usage to break abi and restore it if someone complains? If not, I guess it means that if I keep the symbol I have to keep the function?

[dwfreed]

I'm not able to do a proper review right now, but a quick look indicates many of the consumers of rc_getline expect and need the newline dropping semantics. The sheer quantity suggests it would be better to just use rc_getline as a wrapper around getline to drop the newline, otherwise you will have to implement that in several places, which seems error prone and a waste of effort.