source: tools/PlotTempsViaGnuplot/main.c@ 106

#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <time.h>
 int main(int argc, char *argv[])
{
        
        FILE *plotfile;

        char tempFilename[80];
        long startTime=1246582381;
        char usingStr[40];
        
        if (argc < 3) {
                fprintf (stderr, "usage: plot <filename.slow> Starttimemodifier e.g. 3600 \n");
                return -1;
                }
        if (argc > 3) {
                fprintf (stderr, "too many arguments: usage: plot <filename.slow> Starttimemodifier e.g. 300\n");
                return -1;
                }


        time_t rawtime;
        struct tm * timeinfo;

        time ( &rawtime );
        timeinfo = localtime ( &rawtime );

        startTime = (long)rawtime;
        strcpy(tempFilename, argv[1]);
        
        startTime -= atoi(argv[2]);

        plotfile = fopen ("plot_t.plt","w");
        
        
        if (plotfile!=NULL)
        {
                fputs ("set title 'Temperatures'\n"
                        "set xlabel 'time sec '\n"
                        "set ylabel 'T in C '\n"
                        "set grid\n"
                ,plotfile);

        sprintf(usingStr, "($10>\%d ? $10-\%d : 1/0)", startTime, startTime);
        
        fputs("plot ",plotfile);
        
        fprintf(plotfile, "\"%s\" using %s:12 title 'water out' with points"
                                ,tempFilename
                                ,usingStr
                                );      
        
        fputs(", \\\n", plotfile);
        fprintf(plotfile, "\"%s\" using %s:13 title 'upper right' with points" 
                                ,tempFilename
                                ,usingStr
                                );      
        fputs(", \\\n", plotfile);
        fprintf(plotfile, "\"%s\" using %s:14 title 'upper left' with points" 
                                ,tempFilename
                                ,usingStr
                                );      
        fputs(", \\\n", plotfile);
        fprintf(plotfile, "\"%s\" using %s:15 title 'lower left' with points" 
                                ,tempFilename
                                ,usingStr
                                );      
        fputs(", \\\n", plotfile);
        fprintf(plotfile, "\"%s\" using %s:16 title 'lower right' with points" 
                                ,tempFilename
                                ,usingStr
                                );      
        fputs(", \\\n", plotfile);
        fprintf(plotfile, "\"%s\" using %s:17 title 'water in' with points" 
                                ,tempFilename
                                ,usingStr
                                );      
        fputs(", \\\n", plotfile);
        fprintf(plotfile, "\"%s\" using %s:18 title 'humidity temp' with points" 
                                ,tempFilename
                                ,usingStr
                                );      
        fputs("\n", plotfile);

        fputs("pause -1 \"Hit any key or press OK to continue ...\"\n",plotfile);

        fclose (plotfile);
        }
        
        system("gnuplot plot_t.plt");

        system("rm plot_t.plt");
        return 0;       
}