Working on more example usages of io functions for ch25

ex24_iofunctions.c

@@ -2,16 +2,56 @@
 #include "dbg.h"
 
 
-int main(int argc, char *argv[])
+int fscanf_example01()
 {
-    printf("Reading from stdin: <a:number> <b:number> <c:letter>\n");
     int a, b, rc;
     char c;
+    printf("Reading from stdin: <a:number> <b:number> <c:letter>\n> ");
     rc = fscanf(stdin, "%d %d %c", &a, &b, &c);
     check(rc == 3, "Failed to read from stdin.");
 
     printf("Read in: a=%d b=%d c=%c\n", a, b, c);
 
+    return 1;
+
+error:
+    return 0;
+}
+
+
+int fscanf_example02()
+{
+    int a, b, rc;
+    char c;
+    char filename[1024];
+    FILE *fp;
+
+    printf("Provide filename from which to inputs\n> ");
+    rc = fscanf(stdin, "%s", filename);
+    check(rc == 1, "Failed to read filename");
+    fp = fopen(filename, "r");
+    check(fp != NULL, "Failed to open file %s", filename);
+
+    printf("Reading from \"%s\": <a:number> <b:number> <c:letter>\n", filename);
+    rc = fscanf(fp, "%d %d %c", &a, &b, &c);
+    check(rc == 3, "Failed to read from \"%s\".", filename);
+
+    printf("Read in: a=%d b=%d c=%c\n", a, b, c);
+    rc = fclose(fp);
+    check(rc != EOF, "Failed to close file \"%s\"", filename);
+
+    return 1;
+
+error:
+    return 0;
+}
+
+
+int main(int argc, char *argv[])
+{
+    check(fscanf_example01() == 1, "Fail!");
+    check(fscanf_example02() == 1, "Fail!");
+
     return 0;
 
 error: