diff --git a/man/vcfwriter.Rd b/man/vcfwriter.Rd
index bfcc589..de80752 100644
--- a/man/vcfwriter.Rd
+++ b/man/vcfwriter.Rd
@@ -61,6 +61,7 @@ bw$addFORMAT("GT", "1", "String", "Genotype");
 bw$addSample("NA12878")
 bw$addSample("NA12879")
 s1 <- "chr20\t2006060\trs146931526\tG\tC\t100\tPASS\tAF=0.04\tGT\t1|0\t1|1"
+bw$writeline(s1)
 bw$close()
 file.remove(outvcf)
 }
diff --git a/src/vcf-writer.cpp b/src/vcf-writer.cpp
index a221000..f89a803 100644
--- a/src/vcf-writer.cpp
+++ b/src/vcf-writer.cpp
@@ -46,6 +46,7 @@ using namespace std;
 //' bw$addSample("NA12878")
 //' bw$addSample("NA12879")
 //' s1 <- "chr20\t2006060\trs146931526\tG\tC\t100\tPASS\tAF=0.04\tGT\t1|0\t1|1"
+//' bw$writeline(s1)
 //' bw$close()
 //' file.remove(outvcf)
 class vcfwriter {