A collection of small bits of C code

Here's a collection of experiments I wrote.

License: dedicated to the public domain where permitted by law via CC0.

Contents:
cautenv.c - cauterize the environment
 This cleans the environment, allowing only a small collection of variables
 through if the user specifies. All fds above 2 are closed, and the cwd is
 set to "/" or a user-specified directory.
 Largely an exercise in "how do you clean the environment" and closing all fds,
 but it can be useful if you want to run something under a fixed environment.
 To use it for scripts, set the shebang to "#!/.../cautenv /bin/sh".
 Caveats:
 You must use -c . if you want relative paths to work.
 Scripts that are not in the *new* path (/bin:/usr/bin for nonroot,
 /sbin:/bin:/usr/sbin:/usr/bin for root) must be named by a path that
 can be resolved from the *new* cwd.

tempnftw.c - show hardware temperatures from sysfs
 This is a useable but incomplete experiment in getting hardware temperatures.
 Probably more useful as an example of the nftw() API.
tempglob.c - same, but implemented with glob().
 Slightly more complete.
 As you can see by comparing the two, glob() was the better API here;
 but this does not hold true in all situations.

readdir.c - list files in a directory
 readdir() example that you might find useful if you don't have ls but
 you have a working toolchain (in other words, maybe if you use dd-wrt micro).
 Outputs all files, showing inode numbers and the file type as used by find.
 Not portable: uses the linux d_type extension.

auxtest.c - getauxval() example

socketfork.c - test how many trivial socket-using processes you can spawn.
 Partly intended as a tool to examine effects of a near-forkbomb, but in a
 controlled way. 
 Also a socketpair() example.