utility functions from BSD systems - development files

 This library provides some functions commonly available on BSD systems but
 not on others like GNU systems.
 .
 The currently provided functions are:
 .
  * MD5Data, MD5End, MD5File, MD5FileChunk, MD5Final, MD5Init, MD5Pad,
    MD5Transform, MD5Update.
  * arc4random, arc4random_addrandom, arc4random_buf, arc4random_stir,
    arc4random_uniform.
  * bsd_getopt.
  * dehumanize_number, humanize_number, strtonum, fmtcheck.
  * errc, verrc, vwarnc, warnc.
  * fgetln, flopen, fpurge.
  * getmode, setmode, strmode,
  * getpeereid.
  * getprogname, setprogname, setproctitle.
  * heapsort, radixsort, mergesort, sradixsort.
  * nlist (ELF and a.out support).
  * pidfile_open, pidfile_write, pidfile_close, pidfile_remove.
  * readpassphrase.
  * reallocf.
  * strlcpy, strlcat.
  * strnvis, strnunvis, strunvis, strunvisx, strvis, strvisx, unvis, vis.
 .
 Also included are some queue macro definitions not present on includes
 from glibc.