2:  #include <petscsys.h>

  4: /*@C
  5:      PetscPopUpSelect - Pops up a windows with a list of choices; allows one to be chosen

  7:      Collective on MPI_Comm

  9:      Input Parameters:
 10: +    comm - MPI communicator, all processors in communicator must call this but input
 11:             from first communicator is the only one that is used
 12: .    machine - location to run popup program or NULL
 13: .    title - text to display above choices
 14: .    n - number of choices
 15: -    choices - array of strings

 17:      Output Parameter:
 18: .    choice - integer indicating which one was selected

 20:      Level: developer

 22:      Notes:
 23:        Uses DISPLAY variable or -display option to determine where it opens the window

 25:        Currently this uses a file ~username/.popuptmp to pass the value back from the
 26:        xterm; hence this program must share a common file system with the machine
 27:        parameter passed in below.

 29:    Concepts: popup
 30:    Concepts: user selection
 31:    Concepts: menu

 33: @*/
 34: PetscErrorCode  PetscPopUpSelect(MPI_Comm comm,const char *machine,const char *title,int n,const char **choices,int *choice)
 35: {
 36:   PetscMPIInt    rank;
 37:   int            i,rows = n + 2;
 38:   size_t         cols,len;
 39:   char           buffer[2048],display[256],geometry[64];
 40:   FILE           *fp;

 44:   if (!title) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_NULL,"Must pass in a title line");
 45:   if (n < 1) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONG,"Must pass in at least one selection");
 46:   if (n == 1) {*choice = 0; return(0);}

 48:   PetscStrlen(title,&cols);
 49:   for (i=0; i<n; i++) {
 50:     PetscStrlen(choices[i],&len);
 51:     cols = PetscMax(cols,len);
 52:   }
 53:   cols += 4;
 54:   sprintf(geometry," -geometry %dx%d ",(int)cols,rows);
 55:   PetscStrcpy(buffer,"xterm -bw 100 -bd blue +sb -display ");
 56:   PetscGetDisplay(display,128);
 57:   PetscStrcat(buffer,display);
 58:   PetscStrcat(buffer,geometry);
 59:   PetscStrcat(buffer," -e ${PETSC_DIR}/bin/popup ");

 61:   PetscStrcat(buffer,"\"");
 62:   PetscStrcat(buffer,title);
 63:   PetscStrcat(buffer,"\" ");
 64:   for (i=0; i<n; i++) {
 65:     PetscStrcat(buffer,"\"");
 66:     PetscStrcat(buffer,choices[i]);
 67:     PetscStrcat(buffer,"\" ");
 68:   }
 69: #if defined(PETSC_HAVE_POPEN)
 70:   PetscPOpen(comm,machine,buffer,"r",&fp);
 71:   PetscPClose(comm,fp,NULL);
 72:   MPI_Comm_rank(comm,&rank);
 73:   if (!rank) {
 74:     FILE *fd;

 76:     PetscFOpen(PETSC_COMM_SELF,"${HOMEDIRECTORY}/.popuptmp","r",&fd);
 77:     if (fscanf(fd,"%d",choice) != 1) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_SYS,"fscanf() could not read numeric choice");
 78:     *choice -= 1;
 79:     if (*choice < 0 || *choice > n-1) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Selection %d out of range",*choice);
 80:     PetscFClose(PETSC_COMM_SELF,fd);
 81:   }
 82: #else
 83:   SETERRQ(PETSC_COMM_SELF,PETSC_ERR_SUP_SYS,"Cannot run external programs on this machine");
 84: #endif
 85:   MPI_Bcast(choice,1,MPI_INT,0,comm);
 86:   return(0);
 87: }