Same for string handling/processing, there are specialized libraries out there which do a specific job better than the rather generic standard library functions (this is also true for the C++ stdlib), one just has to find those libraries.
PS: I don't think that a "batteries included" standard library (like python has) would even make sense for C, such a library would need to be opinionated by definition, better to keep (too many) opinions out of the standard, as this road just leads to another C++ ;)
I actually can't think of a lot of these that are super common across projects.
ICU is probably the most notable one, with its particular focus on unicode correctness.
A lot of large projects end up writing their own string library of sorts.
There isn't a universally recognized "standard library replacement" (and people argue about what parts of the standard library they don't like), but here:
https://stackoverflow.com/questions/486383/safer-alternative...
are a few options:
* Glib (the basis for Gtk): https://developer.gnome.org/glib/stable/glib.html
* The Apache Portable Runtime (APR): http://apr.apache.org/
Caveat: I haven't used them.
What is the standard library for the C which ends all the other standards libs?