diff --git a/src/gausskernel/cbb/communication/libcomm_core/mc_tcp.cpp b/src/gausskernel/cbb/communication/libcomm_core/mc_tcp.cpp
index ac2ae21c9..f0c5b7854 100644
--- a/src/gausskernel/cbb/communication/libcomm_core/mc_tcp.cpp
+++ b/src/gausskernel/cbb/communication/libcomm_core/mc_tcp.cpp
@@ -234,6 +234,19 @@ static void mc_tcp_do_listen(int fd, int backlog)
     }
 }
 
+ /*
+function name: mc_tcp_read_block
+description: This function receives data from the other end of TCP in a blocking manner.
+arguments: The first argument indicates the specific socket that has been established.
+				   The second argument is a pointer to memory area, we use it to store received data.
+                   The third argument is byte length of the memory area pointed to by the data pointer.
+                   The fourth argument specifies additional operations in addition to the read operation.
+return value: If there is no error, it returns the byte length of the successfully read data. If an error
+					 occurs, return - 1.
+note: When the data is read successfully, the byte length of the data is greater than 0.
+date: 2022/8/10
+contact tel: 18720816902
+*/
 int mc_tcp_read_block(int fd, void* data, int size, int flags)
 {
 #ifdef LIBCOMM_FAULT_INJECTION_ENABLE
@@ -304,6 +317,19 @@ int mc_tcp_read_block(int fd, void* data, int size, int flags)
     return (size_t)nbytes;
 }
 
+/*
+function name: mc_tcp_read_nonblock
+description: This function receives data from the other end of TCP in a non blocking manner.
+arguments: The first argument indicates the specific socket that has been established.
+				   The second argument is a pointer to memory area, we use it to store received data.
+                   The third argument is byte length of the memory area pointed to by the data pointer.
+                   The fourth argument specifies additional operations in addition to the read operation.
+return value: If the error type is one of the errors represented by EAGAIN, EWOULDBLOCK and EINTR, it returns 0;
+					 other error types return - 1; if there is no error, it returns the byte length of the successfully read data.
+note: When the data is read successfully, the byte length of the data is greater than 0.
+date: 2022/8/10
+contact tel: 18720816902
+*/
 int mc_tcp_read_nonblock(int fd, void* data, int size, int flags)
 {
 #ifdef LIBCOMM_FAULT_INJECTION_ENABLE