Syntax highlight two types of keywords.

.vscode/settings.json

@@ -0,0 +1,5 @@
+{
+    "files.associations": {
+        "termios.h": "c"
+    }
+}

editor.c

@@ -44,7 +44,9 @@ enum editorHighlight {
     HL_COMMENT,
     HL_STRING,
     HL_NUMBER,
-    HL_MATCH
+    HL_MATCH,
+    HL_KEYWORD1,
+    HL_KEYWORD2
 };
 
 /*** data ***/
@@ -54,6 +56,7 @@ struct editorSyntax {
     char **filematch;
     int flags;
     char *singleline_comment_start; // single comment line pattern for this language
+    char **keywords;
 };
 
 typedef struct editorrow {
@@ -85,12 +88,20 @@ struct editorConfig {
 /*** filetypes ***/
 char *C_HL_extensions[] = { ".c", ".h", ".cpp", NULL };
 
+char *C_HL_keywords[] = {
+    "switch", "if", "while", "for", "break", "continue", "return", "else",
+    "struct", "union", "typedef", "static", "enum", "class", "case",
+    "int|", "long|", "double|", "float|", "char|", "unsigned|", "signed|",
+    "void|", "define", "include", NULL
+};
+
 struct editorSyntax HLDB[] = {
     {
         "c",
         C_HL_extensions,
         HL_HIGHLIGHT_NUMBERS | HL_HIGHLIGHT_STRINGS,
-        "//"
+        "//",
+        C_HL_keywords
     },
 };
 
@@ -253,6 +264,8 @@ void editorUpdateSyntax(editorrow *row) {
 
     if (E.syntax == NULL) return;
 
+    char **keywords = E.syntax->keywords;
+
     char *scs = E.syntax->singleline_comment_start;
     int scs_len = scs ? strlen(scs) : 0;
 
@@ -306,6 +319,25 @@ void editorUpdateSyntax(editorrow *row) {
             }
         }
 
+        if (prev_sep) {
+            int j;
+            for (j = 0; keywords[j]; j++) {
+                int klen = strlen(keywords[j]);
+                int kw2 = keywords[j][klen - 1] == '|';
+                if (kw2) klen--;
+                if (!strncmp(&row->render[i], keywords[j], klen) &&
+                    is_separator(row->render[i + klen])) {
+                    memset(&row->hl[i], kw2 ? HL_KEYWORD2 : HL_KEYWORD1, klen);
+                    i += klen;
+                    break;
+                }
+            }
+            if (keywords[j] != NULL) {
+                prev_sep = 0;
+                continue;
+            }
+        }
+
         prev_sep = is_separator(c);
         i++;
     }
@@ -316,10 +348,14 @@ int editorSyntaxToColor(int hl) {
         case HL_NUMBER: 
             return 32;
         case HL_MATCH: // search query match
-            return 31;
+            return 91;
         case HL_STRING: 
             return 33;
         case HL_COMMENT: 
+            return 92;
+        case HL_KEYWORD1: 
+            return 31;
+        case HL_KEYWORD2: 
             return 34;
         default: 
             return 37;