add example

src/manually_ingest.c

+#include <fluent-bit.h>
+
+#define JSON_1   "[1449505010, {\"key1\": \"some value\"}]"
+#define JSON_2   "[1449505620, {\"key1\": \"some new value\"}]"
+
+int main()
+{
+    int ret;
+    int in_ffd;
+    int out_ffd;
+    flb_ctx_t *ctx;
+
+    /* Create library context */
+    ctx = flb_create();
+    if (!ctx) {
+        return -1;
+    }
+
+    /* Enable the input plugin for manual data ingestion */
+    in_ffd = flb_input(ctx, "lib", NULL);
+    if (in_ffd == -1) {
+        flb_destroy(ctx);
+        return -1;
+    }
+
+    /* Enable output plugin 'stdout' (print records to the standard output) */
+    out_ffd = flb_output(ctx, "stdout", NULL);
+    if (out_ffd == -1) {
+        flb_destroy(ctx);
+        return -1;
+    }
+
+    /* Start the engine */
+    ret = flb_start(ctx);
+    if (ret == -1) {
+        flb_destroy(ctx);
+        return -1;
+    }
+
+    /* Ingest data manually */
+    flb_lib_push(ctx, in_ffd, JSON_1, sizeof(JSON_1) - 1);
+    flb_lib_push(ctx, in_ffd, JSON_2, sizeof(JSON_2) - 1);
+
+    /* Stop the engine (5 seconds to flush remaining data) */
+    flb_stop(ctx);
+
+    /* Destroy library context, release all resources */
+    flb_destroy(ctx);
+
+    return 0;
+}
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