The difference of Linux common functions __oracle

One, execl execv excle execve EXECLP EXECVP The difference is:

1, the program file to be executed is the file name or path name;

2, the new program parameters are listed or by an array of pointers to reference;

3. Pass the calling process environment to the new program or assign a new environment to the new program.

the difference of wait waitpid function

Wait will block until the first termination of the existing subprocess; (Excerpt from UNIX Network programming volume P110: Creating a signal handler function is not sufficient to prevent zombie processes from appearing)

Waitpid waits for which process to terminate and chooses whether to tell the kernel to be blocked in the absence of the aborted subprocess.

The close function and the shutdown function (excerpted from UNIX Network programming volume a p136)

Close sets the reference count of the descriptor down by one and closes the socket only when the count changes to 0 o'clock. The shutdown can send a fin regardless of the reference count to excite TCP's normal connection termination sequence;

Close terminates reading and writing data transfer in two directions. Now that TCP is Full-duplex, sometimes we need to tell the right end that the data has been sent, even if it's on the right side, there's still data to send to us.