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Full Discussion: Help with Mkfifo and exec
Top Forums Programming Help with Mkfifo and exec Post 302469509 by dano88 on Saturday 6th of November 2010 05:15:41 PM
Old 11-06-2010
Help with Mkfifo and exec
Hello guys!

I am doing a project for the university and I have to do that a process has to create several children through fork(). The father process sends a pathname to each one through exec and the children must send to the father a list with the files from each directory.

The father is waiting and the children don't send anything. I must to do the pipe with mkfifo. I am trying to send text from the children but nothing happens. This is the code that I have wroten:


Code:
struct stat buf;
 mkfifo(NOMBREFIFO, S_IRWXU);
    while (--argc>0){
        stat (argv[argc], &buf);
        if (S_ISDIR(buf.st_mode)){
            pid = fork();
            
            if (pid<0) fprintf (stderr, "error %d", errno); 
            if (pid==0) printf ("hhhhhhhhh");
            if (pid==0 && (exec=execl ("./listarordenado", argv[argc], NULL))<0) fprintf (stderr, "error %d", errno);
            if (pid>0 && wait(&status) && waitpid (pid, &status, 0)){
                printf ("ssssssssss");
                 while(TRUE) {
                      fp=open(NOMBREFIFO,O_RDONLY);
                      nbytes=read(fp,buffer,TAM_BUF-1);
                      buffer[nbytes]='\0';
                      printf("%d Cadena recibida: %s \n",i, buffer);
                      close(fp);
                      i++;
                }
                 }
         }
      } 


/////***code of listarordenado*//


for (i=0; i<50; i++){
        if ((fp=open(NOMBREFIFO,O_WRONLY))==-1)
            perror("fopen");
          else {    
                descr=write(fp,argv[1],strlen(argv[1]));
        }
         
      close(fp);
    }

thanks,
daniel
 

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LEARN ABOUT DEBIAN

gedcom::individual

Gedcom::Individual(3pm) 				User Contributed Perl Documentation				   Gedcom::Individual(3pm)

NAME

       Gedcom::Individual - a module to manipulate Gedcom individuals

       Version 1.16 - 24th April 2009

SYNOPSIS

	 use Gedcom::Individual;

	 my $name = $i->name;
	 my @rel = $i->father;
	 my @rel = $i->mother;
	 my @rel = $i->parents;
	 my @rel = $i->husband;
	 my @rel = $i->wife;
	 my @rel = $i->spouse;
	 my @rel = $i->siblings;
	 my @rel = $i->brothers;
	 my @rel = $i->sisters;
	 my @rel = $i->children;
	 my @rel = $i->sons;
	 my @rel = $i->daughters;
	 my @rel = $i->descendents;
	 my @rel = $i->ancestors;
	 my $ok  = $i->delete;

	 my @fam = $i->famc;
	 my @fam = $i->fams;

DESCRIPTION

       A selection of subroutines to handle individuals in a gedcom file.

       Derived from Gedcom::Record.

HASH MEMBERS

       None.

METHODS

   name
	 my $name = $i->name;

       Return the name of the individual, with spaces normalised.

   cased_name
	 my $cased_name = $i->cased_name;

       Return the name of the individual, with spaces normalised, and surname in upper case.

   surname
	 my $surname = $i->surname;

       Return the surname of the individual.

   given_names
	 my $given_names = $i->given_names;

       Return the given names of the individual, with spaces normalised.

   soundex
	 my $soundex = $i->soundex;

       Return the soundex code of the individual.  This function is only available if Text::Soundex.pm is available.

   sex
	 my $sex = $i->sex;

       Return the sex of the individual, "M", "F" or "U".

   Individual functions
	 my @rel = $i->father;
	 my @rel = $i->mother;
	 my @rel = $i->parents;
	 my @rel = $i->husband;
	 my @rel = $i->wife;
	 my @rel = $i->spouse;
	 my @rel = $i->siblings;
	 my @rel = $i->older_siblings;
	 my @rel = $i->younger_siblings;
	 my @rel = $i->brothers;
	 my @rel = $i->sisters;
	 my @rel = $i->children;
	 my @rel = $i->sons;
	 my @rel = $i->daughters;
	 my @rel = $i->descendents;
	 my @rel = $i->ancestors;

       Return a list of individuals related to $i.

       Each function, even those with a singular name such as father(), returns a list of individuals holding that relation to $i.

       More complex relationships can easily be found using the map function.  eg:

	 my @grandparents = map { $_->parents } $i->parents;

   delete
	 my $ok  = $i->delete;

       Delete $i from the data structure.

       This function will also set $i to undef.  This is to remind you that the individual cannot be used again.

       Returns true iff $i was successfully deleted.

   Family functions
	 my @fam = $i->famc;
	 my @fam = $i->fams;

       Return a list of families to which $i belongs.

       famc() returns those families in which $i is a child.  fams() returns those families in which $i is a spouse.

perl v5.14.2							    2012-04-12						   Gedcom::Individual(3pm)
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