diff --git a/cmake/Libraries.cmake b/cmake/Libraries.cmake
index 0fa995afc..a92287573 100644
--- a/cmake/Libraries.cmake
+++ b/cmake/Libraries.cmake
@@ -121,31 +121,6 @@ macro(configure_unix_libs)
     message(FATAL_ERROR "Missing posix sigwait")
   endif()
 
-  check_function_exists(inet_aton HAVE_INET_ATON)
-
-  # For some reason, the check_function_exists macro doesn't detect the
-  # inet_aton on some pure Unix platforms (e.g. sunos5). So we need to do a more
-  # detailed check and also include some extra libs.
-  if(NOT HAVE_INET_ATON)
-    set(CMAKE_REQUIRED_LIBRARIES nsl)
-
-    check_c_source_compiles(
-      "#include <arpa/inet.h>\n int main() { inet_aton (0, 0); }"
-      HAVE_INET_ATON_ADV)
-
-    set(CMAKE_REQUIRED_LIBRARIES)
-
-    if(HAVE_INET_ATON_ADV)
-      # Override the previous fail.
-      set(HAVE_INET_ATON 1)
-
-      # Assume that both nsl and socket will be needed, it seems safe to add
-      # socket on the back of nsl, since socket only ever needed when nsl is
-      # needed.
-      list(APPEND libs nsl socket)
-    endif()
-  endif()
-
   # pthread is used on both Linux and Mac
   check_library_exists("pthread" pthread_create "" HAVE_PTHREAD)
   if(HAVE_PTHREAD)
diff --git a/src/lib/Config.h.in b/src/lib/Config.h.in
index 9a3036890..7197fe893 100644
--- a/src/lib/Config.h.in
+++ b/src/lib/Config.h.in
@@ -7,9 +7,6 @@
 
 // clang-format off
 
-/* Define if you have the `inet_aton` function. */
-#cmakedefine HAVE_INET_ATON @HAVE_INET_ATON@
-
 /* Define to 1 if you have the <X11/extensions/Xrandr.h> header file. */
 #cmakedefine HAVE_X11_EXTENSIONS_XRANDR_H @HAVE_X11_EXTENSIONS_XRANDR_H@
 
diff --git a/src/lib/arch/unix/ArchNetworkBSD.cpp b/src/lib/arch/unix/ArchNetworkBSD.cpp
index c0833999f..c2ad0e129 100644
--- a/src/lib/arch/unix/ArchNetworkBSD.cpp
+++ b/src/lib/arch/unix/ArchNetworkBSD.cpp
@@ -25,10 +25,6 @@
 #include <netinet/tcp.h>
 #endif
 
-#if !HAVE_INET_ATON
-#include <stdio.h>
-#endif
-
 static const int s_family[] = {
     PF_UNSPEC,
     PF_INET,
@@ -37,27 +33,6 @@ static const int s_family[] = {
 
 static const int s_type[] = {SOCK_DGRAM, SOCK_STREAM};
 
-#if !HAVE_INET_ATON
-// parse dotted quad addresses.  we don't bother with the weird BSD'ism
-// of handling octal and hex and partial forms.
-static in_addr_t inet_aton(const char *cp, struct in_addr *inp)
-{
-  unsigned int a, b, c, d;
-  if (sscanf(cp, "%u.%u.%u.%u", &a, &b, &c, &d) != 4) {
-    return 0;
-  }
-  if (a >= 256 || b >= 256 || c >= 256 || d >= 256) {
-    return 0;
-  }
-  unsigned char *incp = (unsigned char *)inp;
-  incp[0] = (unsigned char)(a & 0xffu);
-  incp[1] = (unsigned char)(b & 0xffu);
-  incp[2] = (unsigned char)(c & 0xffu);
-  incp[3] = (unsigned char)(d & 0xffu);
-  return inp->s_addr;
-}
-#endif
-
 //
 // ArchNetworkBSD::Deps
 //