46 lines
916 B
C
46 lines
916 B
C
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/* Simple backend for a Logo like tortoise drawer. */
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#include <stdlib.h>
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#include <stdio.h>
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#include <unistd.h>
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static const int WIDTH = 10;
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static const int HEIGHT = 10;
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static FILE*
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start_gnuplot() {
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FILE* output;
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int pipes[2];
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pid_t pid;
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pipe(pipes);
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pid = fork();
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if (!pid) {
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dup2 (pipes[0], STDIN_FILENO);
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execlp ("gnuplot", NULL);
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return; /* Not reached. */
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}
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output = fdopen(pipes[1], "w");
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fprintf (output, "set multiplot\n");
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fprintf (output, "set parametric\n");
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fprintf (output, "set xrange [-%d:%d]\n", WIDTH, WIDTH);
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fprintf (output, "set yrange [-%d:%d]\n", HEIGHT, HEIGHT);
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fprintf (output, "set size ratio -1\n");
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fprintf (output, "unset xtics\n");
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fprintf (output, "unset ytics\n");
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fflush (output);
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return output;
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}
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static FILE* global_output;
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int main(int argc, char *argv[]) {
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global_output = start_gnuplot();
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return EXIT_SUCCESS;
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}
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