c - How to use popen to input and output in the same time? -

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this question has answer here:

i use psuedo-code express want do:

file* fd = popen("/bin/cat", ...); write data stdin of `/bin/cat` using fd; read data stdout of `/bin/cat` using fd;

is possible?

popen() can read new process. if need read , write,

  • create pipe connected new process using pipe().
  • fork new process using fork()
  • redirect process's input , outputs pipes created earlier using dup2()
  • call exec on child process (the new process) using exec family functions

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