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#include <stdio.h>
#include <errno.h>
#include <unistd.h>
int main()
{
  FILE *popen_result;
  char buff[512];
  char *cmd = "lss";
  int temperr = dup(2);               // copy where stderr is at the moment
  freopen("/dev/null", "w", stderr);  // trash stderr reports from popen shell
  popen_result = popen(cmd, "r");
  if( popen_result==NULL )
      printf("Error!\n");
  stderr = fdopen(temperr,"w");       // get back stderr
  perror(cmd);
  if ( feof(popen_result) )
    printf("Already at EOF!\n");
  if ( ferror(popen_result) )
    printf("Already at error!\n");
  int err=1;
  while(fgets(buff, sizeof(buff), popen_result)!=NULL){
        printf(">>> %s", buff);
        err=0;
  }
  if( err==1 )
      printf("Error! Command %s not found\n", cmd);
  if( feof(popen_result) && err==0)
      printf("EOF cmd\n");
  pclose(popen_result);
}