Add example for <kernaux/printf.h>

.gitignore

@@ -33,6 +33,7 @@
 /tests/test*.trs
 
 /examples/cmdline
+/examples/printf
 /tests/multiboot2_print1
 /tests/multiboot2_print2
 /tests/test_cmdline

Makefile.am

@@ -10,6 +10,7 @@ AM_CFLAGS = \
 lib_LIBRARIES = libkernaux.a
 
 TESTS = \
+	examples/printf \
 	tests/test_printf \
 	tests/test_stdlib
 
@@ -57,6 +58,10 @@ examples_cmdline_SOURCES = \
 	$(libkernaux_a_SOURCES) \
 	examples/cmdline.c
 
+examples_printf_SOURCES = \
+	$(libkernaux_a_SOURCES) \
+	examples/printf.c
+
 tests_multiboot2_print1_SOURCES = \
 	$(libkernaux_a_SOURCES) \
 	tests/multiboot2_print1.c

examples/printf.c

@@ -0,0 +1,26 @@
+#include <kernaux/printf.h>
+
+#include <assert.h>
+#include <stdlib.h>
+#include <string.h>
+
+#define BUFFER_SIZE 1024
+
+static char buffer[BUFFER_SIZE];
+static unsigned int buffer_index;
+
+static void my_putchar(const char chr)
+{
+    if (buffer_index >= BUFFER_SIZE) abort();
+    buffer[buffer_index++] = chr;
+}
+
+int main()
+{
+    memset(buffer, '\0', sizeof(buffer));
+    buffer_index = 0;
+    kernaux_printf(my_putchar, "Hello, World!");
+    assert(strcmp(buffer, "Hello, World!") == 0);
+
+    return 0;
+}