double.c backup

chap1/double.c

@@ -0,0 +1,52 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <errno.h>
+#include <ctype.h>
+
+int linenum;
+
+int getword(FILE *, char *, int);
+
+int main(int argc, char *argv[]) {
+    int i;
+
+    for (i = 1; i < argc; i++) {
+        FILE *fp = fopen(argv[i], "r");
+        if (fp == NULL) {
+            fprintf(
+                stderr,
+                "%s: can't open '%s' (%s)\n",
+                argv[0], argv[i], strerror(errno)
+            );
+        } else {
+            doubleword(argv[i], fp);
+            fclose(fp);
+        }
+    }
+    if (argc == 1) doubleword(NULL, stdin);
+    return EXIT_SUCCESS;
+}
+
+int getword(FILE *fp, char *buf, int size) {
+    int c;
+    c = getc(fp);
+
+    // Scan forward to nonspace or EOF.
+    for ( ; c != EOF && isspace(c); c = getc(fp))
+        if (c == '\n')
+            linenum++;
+
+    // Copy word to buff.
+    {
+        int i = 0;
+        for ( ; c != EOF && !isspace(c); c = getc(fp))
+            if (i < size - 1)
+                buf[i++] = tolower(c);
+        if (i < size)
+            buf[i] = '\0';
+    }
+
+    if (c != EOF)
+        ungetc(c, fp);
+    return  buf[0] != '\0';
+}