feat: add -h, update docs

README.md

@@ -16,15 +16,18 @@ To not rely on a Windows VM for configuring the scanner, I sniffed the USB traff
 
 First of all, compile the program using `make`.  It depends only on `libusb-1.0`.
 
-The configuration strings need to be provided as command line arguments.  You can provide multiple:
+The configuration commands can be provided either as CLI arguments or via stdin; if CLI commands are present, stdin is ignrored.
 
 ```
-usage: ./honeywell-config [-v vendor] [-p product] [-o] [-r] [-d] command1 [command2 [... commandN]]
+Usage: ./honeywell-config [-v vendor] [-p product] [-1] [-r] [-d] [-i infile] [-o outfile] [command1 [... commandN]]
   -v vendor     USB vendor ID of the barcode scanner
   -p product	USB product ID of the barcode scanner
-  -o            Print response on one line, rather than one token per line
+  -1            Print response on one line, rather than one token per line
   -r            Reset device after configuration
   -d            Debug mode (more verbose output)
+  -i infile     Read input from infile instead of stdin
+  -o outfile    Write output to outfile instead of stdout
+  -h            Show this help
 ```
 
 If no vendor ID or product ID is provided, the following set of IDs is tried:
@@ -37,10 +40,31 @@ USB serial mode (`0c2e:0b0a`) is skipped because USB configuration does not seem
 
 For the actual configuration commands, please refer to your scanner's manual.  Here are some examples.
 
+### Dump Current Config
+
+When invoked without any command or input file, the command `?.` is run, which dumps the current config of the barcode scanner:
+
+```shell-session
+$ ./honeywell-config
+BEPFQ12550.
+BEPFQ2100.
+...
+AXXMOD0.
+```
+
+Please not that this dump can not be restored as-is - it contains some commands that are not really config options, among them the factor reset commands `DEFOVR.` and `DEFALT.`
+
+### Retrieve Firmware Version and Build Date
+
+```shell-session
+$ ./honeywell-config 'REV?'
+REV_SW13718|/tags/BE000186BAA,_TDFeb 11 2014,_WABE000186BAA,INF.
+```
+
 ### Factory Reset
 
-```
-$ ./honeywell-config DEFOVR. DEFALT.
+```shell-session
+$ ./honeywell-config DEFOVR DEFALT
 DEFOVR.
 DEFALT.
 ```
@@ -49,22 +73,22 @@ DEFALT.
 
 USBHID:
 
-```
-$ ./honeywell-config PAP131.
+```shell-session
+$ ./honeywell-config PAP131
 PAP131.
 ```
 
 Keyboard (PC):
 
-```
-$ ./honeywell-config PAP124.
+```shell-session
+$ ./honeywell-config PAP124
 PAP124.
 ```
 
 Keyboard (Apple):
 
-```
-$ ./honeywell-config PAP125.
+```shell-session
+$ ./honeywell-config PAP125
 PAP124.
 ```
 
@@ -74,8 +98,8 @@ Please note that when switching modes, the scanner restarts on its own, so some
 
 The following adds the string `FCKAFD ` (ASCII hex `46 43 4B 41 46 44 20`) in front of every scanned barcode:
 
-```
-$ ./honeywell-config PREBK29946434B41464420.
+```shell-session
+$ ./honeywell-config PREBK29946434B41464420
 PREBK29946434B41464420.
 ```
 
@@ -97,7 +121,7 @@ On the USB config interface, all of that goes into a single string instead.
 ### Query Current Beeper Settings
 
 ```
-$ ./honeywell-config 'BEP?.'
+$ ./honeywell-config 'BEP?'
 BEPFQ12550,FQ2100,RPT1,ERR1,BEP1,BIP0,LVL0,EXZ,GRX,EXE,DFT,LED1.
 ```
 

honeywell-config.c

@@ -380,7 +380,7 @@ int main(int argc, char **argv) {
   int opt;
   char *end;
   long parsed;
-  while ((opt = getopt(argc, argv, "v:p:1rdi:o:")) != -1) {
+  while ((opt = getopt(argc, argv, "v:p:1rdi:o:h")) != -1) {
     switch (opt) {
     case 'v':
       end = optarg;
@@ -441,7 +441,7 @@ int main(int argc, char **argv) {
       }
       break;
     default:
-      printf("usage: %s [-v vendor] [-p product] [-1] [-r] [-d] [-i infile] [-o outfile] [command1 [... commandN]]\n", argv[0]);
+      printf("Usage: %s [-v vendor] [-p product] [-1] [-r] [-d] [-i infile] [-o outfile] [command1 [... commandN]]\n", argv[0]);
       puts("  -v vendor\tUSB vendor ID of the barcode scanner");
       puts("  -p product\tUSB product ID of the barcode scanner");
       puts("  -1\t\tPrint response on one line, rather than one token per line");
@@ -449,6 +449,7 @@ int main(int argc, char **argv) {
       puts("  -d\t\tDebug mode (more verbose output)");
       puts("  -i infile\tRead input from infile instead of stdin");
       puts("  -o outfile\tWrite output to outfile instead of stdout");
+      puts("  -h \t\tShow this help");
       return 1;
     }
   }