Allow multiple keystrokes at the same time

[keystroke-timestamps] / keystroke-timestamps.c

diff --git a/keystroke-timestamps.c b/keystroke-timestamps.c
index 5a27279660103f6503cfc8066be0096d24f1f235..31086788cf34bec292b0b53512e05315fd569eb1 100644 (file)
--- a/keystroke-timestamps.c
+++ b/keystroke-timestamps.c
@@ -9,6 +9,12 @@
 #include <sys/select.h>
 #include <unistd.h>
 
+// This constant is defined in include/uapi/linux/input-event-codes.h
+#ifndef EV_KEY
+#define EV_KEY      0x01
+#endif
+
+
 int main (int argc, char **argv)
 {
   int print_usec = 0;
@@ -34,6 +40,7 @@ int main (int argc, char **argv)
     if (c != 0) exit(EX_USAGE);
   }
 
+  /* Open output file */
   FILE *output_file;
   if (output == NULL) {
     output_file = stdout;
@@ -44,6 +51,7 @@ int main (int argc, char **argv)
     }
   }
 
+  /* Open device inputs */
   fd_set all_inputs;
   FD_ZERO(&all_inputs);
   int maxfd = 0;
@@ -67,10 +75,11 @@ int main (int argc, char **argv)
   }
   globfree(&glob_result);
 
+  /* Report keystroke timestamps */
   struct input_event i;
   while (1) {
     fd_set ready_inputs = all_inputs;
-    if (select(maxfd+1, &ready_inputs, NULL, NULL, NULL) != 1) {
+    if (select(maxfd+1, &ready_inputs, NULL, NULL, NULL) < 1) {
       err(EX_IOERR, "select");
     }
     for (int fd=0; fd <= maxfd; fd++) {
@@ -82,7 +91,7 @@ int main (int argc, char **argv)
         if (read_return != sizeof(i)) {
           errx(EX_IOERR, "Unexpected EOF");
         }
-        if (i.type == 1 && i.value == 1) {
+        if (i.type == EV_KEY && i.value == 1) {
           if (print_usec) {
             fprintf(output_file, "%ld.%06ld\n", i.time.tv_sec, i.time.tv_usec);
           } else {