Actual source code: pdisplay.c

 2:  #include petsc.h
 3:  #include petscsys.h
  4: #include <stdarg.h>
  5: #if defined(PETSC_HAVE_STDLIB_H)
  6: #include <stdlib.h>
  7: #endif
  8: #include "petscfix.h"

 12: /*@C
 13:      PetscOptionsGetenv - Gets an environmental variable, broadcasts to all
 14:           processors in communicator from first.

 16:      Collective on MPI_Comm

 18:    Input Parameters:
 19: +    comm - communicator to share variable
 20: .    name - name of environmental variable
 21: -    len - amount of space allocated to hold variable

 23:    Output Parameters:
 24: +    flag - if not PETSC_NULL tells if variable found or not
 25: -    env - value of variable

 27:   Level: advanced

 29:    Notes:
 30:     You can also "set" the environmental variable by setting the options database value
 31:     -name "stringvalue" (with name in lower case). If name begins with PETSC_ this is 
 32:     discarded before checking the database. For example, PETSC_VIEWER_SOCKET_PORT would 
 33:     be given as -viewer_socket_port 9000

 35:     If comm does not contain the 0th process in the MPIRUN it is likely on
 36:     many systems that the environmental variable will not be set unless you
 37:     put it in a universal location like a .chsrc file

 39: @*/
 40: PetscErrorCode PetscOptionsGetenv(MPI_Comm comm,const char name[],char env[],size_t len,PetscTruth *flag)
 41: {
 43:   PetscMPIInt    rank;
 44:   char           *str,work[256];
 45:   PetscTruth     flg = PETSC_FALSE,spetsc;
 46: 

 49:   /* first check options database */
 50:   PetscStrncmp(name,"PETSC_",6,&spetsc);
 51: 
 52:   PetscStrcpy(work,"-");
 53:   if (spetsc) {
 54:     PetscStrcat(work,name+6);
 55:   } else {
 56:     PetscStrcat(work,name);
 57:   }
 58:   PetscStrtolower(work);
 59:   if (env) {
 60:     PetscOptionsGetString(PETSC_NULL,work,env,len,&flg);
 61:     if (flg) {
 62:       if (flag) *flag = PETSC_TRUE;
 63:     } else { /* now check environment */
 64:       PetscMemzero(env,len*sizeof(char));

 66:       MPI_Comm_rank(comm,&rank);
 67:       if (!rank) {
 68:         str = getenv(name);
 69:         if (str) flg = PETSC_TRUE;
 70:         if (str && env) {PetscStrncpy(env,str,len);}
 71:       }
 72:       MPI_Bcast(&flg,1,MPI_INT,0,comm);
 73:       MPI_Bcast(env,len,MPI_CHAR,0,comm);
 74:       if (flag) *flag = flg;
 75:     }
 76:   } else {
 77:     PetscOptionsHasName(PETSC_NULL,work,flag);
 78:   }
 79:   return(0);
 80: }

 82: /*
 83:      PetscSetDisplay - Tries to set the X windows display variable for all processors.
 84:                        The variable PetscDisplay contains the X windows display variable.

 86: */
 87: static char PetscDisplay[256];

 91: PetscErrorCode PetscSetDisplay(void)
 92: {
 94:   PetscMPIInt    size,rank;
 95:   PetscTruth     flag;
 96:   char           *str,display[256];

 99:   PetscMemzero(display,256*sizeof(char));
100:   PetscOptionsGetString(PETSC_NULL,"-display",PetscDisplay,256,&flag);
101:   if (flag) return(0);

103:   MPI_Comm_size(PETSC_COMM_WORLD,&size);
104:   MPI_Comm_rank(PETSC_COMM_WORLD,&rank);
105:   if (!rank) {
106:     str = getenv("DISPLAY");
107:     if (!str || (str[0] == ':' && size > 1)) {
108:       PetscGetHostName(display,124);
109:       PetscStrcat(display,":0.0");
110:     } else {
111:       PetscStrncpy(display,str,256);
112:     }
113:   }
114:   MPI_Bcast(display,256,MPI_CHAR,0,PETSC_COMM_WORLD);
115:   if (rank) {
116:     str = getenv("DISPLAY");
117:     /* assume that ssh port forwarding is working */
118:     if (str && (str[0] != ':')) {
119:       PetscStrcpy(display,str);
120:     }
121:   }
122:   PetscStrcpy(PetscDisplay,display);
123:   return(0);
124: }

128: /*
129:      PetscGetDisplay - Gets the display variable for all processors.

131:   Input Parameters:
132: .   n - length of string display

134:   Output Parameters:
135: .   display - the display string

137: */
138: PetscErrorCode PetscGetDisplay(char display[],size_t n)
139: {

143:   PetscStrncpy(display,PetscDisplay,n);
144:   return(0);
145: }