41–50 of 58 posts
"The language doesn't come with [a hash table implementation] included" The standard library does come with a half-baked hash table implementation[1] (hcreate/hdestroy/hsearch) that only allows creation of _one_ global hash table. GNU libc[2] adds hcreate_r/hdestroy_r/hsearch_r that allows multiple tables to be created. The APIs are strange and antiquated. On the other hand, the hash table implementation described in…
Earlier quoted context omitted.
The hcreate nonsense is POSIX, not C99, so a conforming C implementation might not include it.
How does junk like this ever get into a standard? Didn't a whole committee of very experienced systems programmers have to sit down and say, "yes, these are routines that i think people will find generally useful"? It looks like the same header, search.h, also includes functions for working with binary trees, where the user passes in the root pointer, and so which support multiple trees: http://pubs.opengroup.org/onl…
I've heard of two possibilities (as a recommendation) for using data structures in C without having to develop them: - BSD queue.h offers linked lists, queues, etc [1]. - UT-hash offers hash tables [2]. I've also read some people being frustrated with them, probably due to the quirky syntax/API. On the plus side (BSD at least) it's just a header file that you can download, include and start using. [1] http://bxr.su/O…
https://attractivechaos.wordpress.com/2008/08/28/comparison-...
(Also provides kbtree.h, ksort.h, kstream.h, kvec.h)
[3] https://attractivechaos.wordpress.com/programs/
Also there are the stb header-only libraries. There is a hash table implementation buried inside stb.h
"The language doesn't come with [a hash table implementation] included" The standard library does come with a half-baked hash table implementation[1] (hcreate/hdestroy/hsearch) that only allows creation of _one_ global hash table. GNU libc[2] adds hcreate_r/hdestroy_r/hsearch_r that allows multiple tables to be created. The APIs are strange and antiquated. On the other hand, the hash table implementation described in…
The hcreate nonsense is POSIX, not C99, so a conforming C implementation might not include it.
Signed,
POSIX_ME_HARDER
I've heard of two possibilities (as a recommendation) for using data structures in C without having to develop them: - BSD queue.h offers linked lists, queues, etc [1]. - UT-hash offers hash tables [2]. I've also read some people being frustrated with them, probably due to the quirky syntax/API. On the plus side (BSD at least) it's just a header file that you can download, include and start using. [1] http://bxr.su/O…
Also, your double hashing scheme has a bug. You identified that it's problematic if hash_b returns 0, but adding 1 to the result doesn't actually solve anything, because now you have the same problem if hash_b returns num_buckets-1.
I've heard of two possibilities (as a recommendation) for using data structures in C without having to develop them: - BSD queue.h offers linked lists, queues, etc [1]. - UT-hash offers hash tables [2]. I've also read some people being frustrated with them, probably due to the quirky syntax/API. On the plus side (BSD at least) it's just a header file that you can download, include and start using. [1] http://bxr.su/O…
I've heard of two possibilities (as a recommendation) for using data structures in C without having to develop them: - BSD queue.h offers linked lists, queues, etc [1]. - UT-hash offers hash tables [2]. I've also read some people being frustrated with them, probably due to the quirky syntax/API. On the plus side (BSD at least) it's just a header file that you can download, include and start using. [1] http://bxr.su/O…
Earlier quoted context omitted.
How does junk like this ever get into a standard? Didn't a whole committee of very experienced systems programmers have to sit down and say, "yes, these are routines that i think people will find generally useful"? It looks like the same header, search.h, also includes functions for working with binary trees, where the user passes in the root pointer, and so which support multiple trees: http://pubs.opengroup.org/onl…
A standards process is frequently about documenting what already exists in common implementations so that there is a specification for future implementations. POSIX was very much one of these processes.