Add Makefile. Remove empty unfold.c.

src/Makefile

@@ -0,0 +1,21 @@
+.POSIX:
+.SUFFIX:
+
+PREFIX = /usr
+
+BINS = \
+	overwrite \
+	strcmp    \
+	vis
+
+all: $(BINS)
+
+install: all
+	install -Dm755 $(BINS) $(DESTDIR)/$(PREFIX)/bin/
+
+clean:
+	rm *.o $(BINS) *~ a.out
+
+.SUFFIX:
+.c.o:
+	cc -c -o $< $(CFLAGS) $(LDFLAGS) 

src/support.h

@@ -44,17 +44,17 @@ void throw(long unsigned int condition, void *info)
     {
     switch(condition)
 	{
-	case UNKNOWN_FAIL: printf("unknown failure\n");
+	case UNKNOWN_FAIL: fprintf(stderr, "unknown failure\n");
 	    exit(UNKNOWN_FAIL);
-	case MALLOC_FAIL: printf("malloc failure\n");
+	case MALLOC_FAIL: fprintf(stderr, "malloc failure\n");
 	    exit(MALLOC_FAIL);
-	case NEEDARG_FAIL: printf("usage: %s\n", (char *) info);
+	case NEEDARG_FAIL: fprintf(stderr, "usage: %s\n", (char *) info);
 	    exit(NEEDARG_FAIL);
-	case FOPEN_FAIL: printf("failed to open: %s\n", (char *) info);
+	case FOPEN_FAIL: fprintf(stderr, "failed to open: %s\n", (char *) info);
 	    exit(FOPEN_FAIL);
-	case WRITE_FAIL: printf("failed to write: %s\n", (char *) info);
+	case WRITE_FAIL: fprintf(stderr, "failed to write: %s\n", (char *) info);
 	    exit(WRITE_FAIL);
-	default: printf("You shouldn't be seeing this.\nSomething is very wrong.\n");
+	default: fprintf(stderr, "You shouldn't be seeing this.\nSomething is very wrong.\n");
 	    exit(-256);
 	}
     }

src/unfold.c

@@ -1 +0,0 @@
-#

src/vis.c

@@ -8,19 +8,18 @@
 
 int main(int argc, char **argv)
     {
-    int i, c;
-    FILE *fp;
-    i = c = 0;
+    int c;
+    c = 0;
 
-    for(;(c = getchar()) != EOF; i++)
+    for(;(c = getchar()) != EOF;)
 	{
-	if(isascii(c) && (c != ' ' && c != '\n' && c != '\t'))
+	if(isascii(c) && !(c == ' ' || c == '\n' || c == '\t'))
 	    {
-	    printf("%c", c);
+	    putc(c, stdout);
 	    }
 	else
 	    {
-	    printf("%.3o", c);
+	    fprintf(stdout, "%.3o", c);
 	    }
 	}