Caution when redirecting stdin/stdout/stderr in C

You must save the original preopened file descriptors using dup(). You then use dup2(), open() to do IO redirection. After done with IO redirection, you need to restore default stdin/stdout/stderr using sdup2() again, otherwise you program cannot interact with STDIO properly as it could before IO redirection! The previous article on this blog shows a good code example on how to do that.

C sample code - Program Using Pipes and IO redirection

• C sample code - Output of one program is input of another program Using Pipes - Source code examples
  Clear and simple good example of using pipes with io redirection and restoring stdout/stdin after finishing pipelining.
  tags: c code sample pipes io redirection restoration

Posted from Diigo. The rest of my favorite links are here.