Added free-running (non-triggered) buffered input example

examples/iio_free_scan.rs

@@ -0,0 +1,53 @@
+// industrial-io/examples/iio_free_scan.rs
+//
+// Simple Rust IIO example.
+// This does buffered reading without using a trigger (free scan).
+//
+// Copyright (c) 2018, Frank Pagliughi
+//
+// Licensed under the MIT license:
+//   <LICENSE or http://opensource.org/licenses/MIT>
+// This file may not be copied, modified, or distributed except according
+// to those terms.
+//
+
+extern crate industrial_io as iio;
+use std::process;
+
+const DFLT_DEV_NAME: &'static str = "44e0d000.tscadc:adc";
+
+
+fn main() {
+    let dev_name = DFLT_DEV_NAME;
+
+    let ctx = iio::Context::new().unwrap_or_else(|_err| {
+        println!("Couldn't open default IIO context");
+        process::exit(1);
+    });
+
+    let dev = ctx.find_device(dev_name).unwrap_or_else(|| {
+        println!("No IIO device named '{}'", dev_name);
+        process::exit(2);
+    });
+
+    for mut chan in dev.channels() {
+        chan.enable();
+    }
+
+    let mut buf = dev.create_buffer(8, false).unwrap_or_else(|err| {
+        eprintln!("Unable to create buffer: {}", err);
+        process::exit(3);
+    });
+
+    println!("Capturing a buffer...");
+    if let Err(err) = buf.refill() {
+        eprintln!("Error filling the buffer: {}", err);
+        process::exit(4);
+    }
+
+    for mut chan in dev.channels() {
+        let data: Vec<u16> = buf.channel_iter::<u16>(&chan).collect();
+        println!("{}: {:?}", chan.id().unwrap_or_default(), data);
+    }
+}
+

src/device.rs

@@ -192,6 +192,15 @@ impl Device {
         }
     }
 
+    /// Creates a buffer for the device.
+    ///
+    /// `sample_count` The number of samples the buffer should hold
+    /// `cyclic` Whether to enable cyclic mode.
+    pub fn create_buffer(&self, sample_count: usize, cyclic: bool) -> Result<Buffer> {
+        let buf = unsafe { ffi::iio_device_create_buffer(self.dev, sample_count, cyclic) };
+        if buf.is_null() { bail!(SysError(Errno::last())); }
+        Ok(Buffer { buf, })
+    }
 }
 
 impl PartialEq for Device {