diff --git a/nonisotropic.cpp b/nonisotropic.cpp
index 3bbc0e36..793e763d 100644
--- a/nonisotropic.cpp
+++ b/nonisotropic.cpp
@@ -88,11 +88,11 @@ EX namespace sn {
     FILE *f = fopen(fname.c_str(), "rb");
     if(!f) f = fopen((rsrcdir + fname).c_str(), "rb");
     if(!f) { addMessage(XLAT("geodesic table missing")); pmodel = mdPerspective; return; }
-    ignore(fread(&PRECX, 4, 1, f));
-    ignore(fread(&PRECY, 4, 1, f));
-    ignore(fread(&PRECZ, 4, 1, f));
+    hr::ignore(fread(&PRECX, 4, 1, f));
+    hr::ignore(fread(&PRECY, 4, 1, f));
+    hr::ignore(fread(&PRECZ, 4, 1, f));
     tab.resize(PRECX * PRECY * PRECZ);
-    ignore(fread(&tab[0], sizeof(compressed_point) * PRECX * PRECY * PRECZ, 1, f));
+    hr::ignore(fread(&tab[0], sizeof(compressed_point) * PRECX * PRECY * PRECZ, 1, f));
     fclose(f);
     loaded = true;    
     }
diff --git a/rogueviz/presentation.cpp b/rogueviz/presentation.cpp
index e18aff78..11e4ef21 100644
--- a/rogueviz/presentation.cpp
+++ b/rogueviz/presentation.cpp
@@ -160,7 +160,7 @@ string gen_latex(presmode mode, string s, int res) {
   string filename = format("latex-cache/%08X.png", hash);
   if(mode == pmStartAll) {
     if(!file_exists(filename)) {
-      system("mkdir latex-cache");
+      hr::ignore(system("mkdir latex-cache"));
       FILE *f = fopen("latex-cache/rogueviz-latex.tex", "w");
       fprintf(f,
         "\\documentclass[border=2pt]{standalone}\n"
@@ -172,9 +172,9 @@ string gen_latex(presmode mode, string s, int res) {
         "\\end{varwidth}\n"
         "\\end{document}\n", s.c_str());
       fclose(f);
-      system("cd latex-cache; pdflatex rogueviz-latex.tex");
+      hr::ignore(system("cd latex-cache; pdflatex rogueviz-latex.tex"));
       string pngline = "cd latex-cache; pdftopng -r " + its(res) + " rogueviz-latex.pdf t";
-      system(pngline.c_str());
+      hr::ignore(system(pngline.c_str()));
       rename("latex-cache/t-000001.png", filename.c_str());
       }
     }
diff --git a/rogueviz/som/analyzer.cpp b/rogueviz/som/analyzer.cpp
index 41dcf7f1..e2dacec4 100644
--- a/rogueviz/som/analyzer.cpp
+++ b/rogueviz/som/analyzer.cpp
@@ -36,13 +36,13 @@ void load_maniset(maniset& m, int scale) {
       m.names.push_back(buf);
     auto& md = m.mdata[buf];
     int N, M;
-    fscanf(f, "%d%d", &N, &M);
+    hr::ignore(fscanf(f, "%d%d", &N, &M));
     println(hlog, "reading ", buf, " of size ", N, " and ", M, " edges");
     md.size = N;
     auto& ed = md.edges;
     for(int i=0; i<M; i++) {
       int a, b;
-      fscanf(f, "%d%d", &a, &b);
+      hr::ignore(fscanf(f, "%d%d", &a, &b));
       ed.emplace_back(a, b);
       }
     md.distances = measures::build_distance_matrix(N, md.edges);
@@ -125,10 +125,10 @@ void analyze_test() {
 
             while(current_row < it) {
               current_row++;
-              for(int i=0; i<No; i++) fscanf(f, "%d", &mapp[i]);
-              int V = 0; fscanf(vor, "%d", &V);
+              for(int i=0; i<No; i++) hr::ignore(fscanf(f, "%d", &mapp[i]));
+              int V = 0; hr::ignore(fscanf(vor, "%d", &V));
               vor_edges.resize(V);
-              for(int i=0; i<V; i++) fscanf(vor, "%d%d", &vor_edges[i].first, &vor_edges[i].second);
+              for(int i=0; i<V; i++) hr::ignore(fscanf(vor, "%d%d", &vor_edges[i].first, &vor_edges[i].second));
               if(mapp.back() == -2) goto next_pair;
               if(current_row == it)
                 edo_recreated = measures::recreate_topology(mapp, edo);
@@ -226,4 +226,4 @@ auto khook = arg::add3("-analyze-test", analyze_test);
 }}
 
 
- 
\ No newline at end of file
+ 
diff --git a/rogueviz/som/tests.cpp b/rogueviz/som/tests.cpp
index f4579e20..300a971e 100644
--- a/rogueviz/som/tests.cpp
+++ b/rogueviz/som/tests.cpp
@@ -800,7 +800,7 @@ bool more = true;
 
 void create_index() {
 
-  system(("mkdir " + som_test_dir).c_str());
+  hr::ignore(system(("mkdir " + som_test_dir).c_str()));
 
   fhstream f(som_test_dir + "index-" + its(current_scale) + ".html", "wt");
 
@@ -958,7 +958,7 @@ void all_pairs(bool one) {
 
   string dir = som_test_dir + "pairs" + cg();
 
-  system(("mkdir -p " + dir + "/img").c_str());  
+  hr::ignore(system(("mkdir -p " + dir + "/img").c_str()));
 
   int sid = 0;
   for(auto s1: shapelist) {
@@ -1093,7 +1093,7 @@ void all_pairs(bool one) {
       }
     }
 
-  system("touch done");  
+  hr::ignore(system("touch done"));
   }
 
 bool verify_distlists = false;