Unable to compile libplot example program from plotutils documentation - c

Question

I'm trying to compile example code that I found in the plotutils documentation. I added the appropriate search path for the plot.h header file and linked the binary to every object file that gets created when you make install plotutils 2.6. I'm on OS X 10.10.3 with Xcode 6.3.2 and I'm a novice when it comes to C programming or using Xcode.
The example code I'm trying to compile is:
#include <stdio.h>
#include <plot.h>
#define MAXORDER 12
void draw_c_curve (plPlotter *plotter, double dx, double dy, int order)
{
if (order >= MAXORDER)
/* continue path along (dx, dy) */
pl_fcontrel_r (plotter, dx, dy);
else
{
draw_c_curve (plotter,
0.5 * (dx - dy), 0.5 * (dx + dy), order + 1);
draw_c_curve (plotter,
0.5 * (dx + dy), 0.5 * (dy - dx), order + 1);
}
}
int main ()
{
plPlotter *plotter;
plPlotterParams *plotter_params;
/* set a Plotter parameter */
plotter_params = pl_newplparams ();
pl_setplparam (plotter_params, "PAGESIZE", "letter");
/* create a Postscript Plotter that writes to standard output */
if ((plotter = pl_newpl_r ("ps", stdin, stdout, stderr,
plotter_params)) == NULL)
{
fprintf (stderr, "Couldn’t create Plotter\n");
return 1;
}
if (pl_openpl_r (plotter) < 0) /* open Plotter */
{
fprintf (stderr, "Couldn’t open Plotter\n");
return 1;
}
pl_fspace_r (plotter, 0.0, 0.0, 1000.0, 1000.0); /* set coor system */
pl_flinewidth_r (plotter, 0.25); /* set line thickness */
pl_pencolorname_r (plotter, "red"); /* use red pen */
pl_erase_r (plotter); /* erase graphics display */
pl_fmove_r (plotter, 600.0, 300.0); /* position the graphics cursor */
draw_c_curve (plotter, 0.0, 400.0, 0);
if (pl_closepl_r (plotter) < 0) /* close Plotter */
{
fprintf (stderr, "Couldn’t close Plotter\n");
return 1;
}
if (pl_deletepl_r (plotter) < 0) /* delete Plotter */
{
fprintf (stderr, "Couldn’t delete Plotter\n");
return 1;
}
return 0;
}
The 2 issues Xcode identifies are:
Undefined symbols for architecture x86_64:
"__pl_z_maybe_output_image", referenced from:
__maybe_output_image in b_defplot.o
ld: symbol(s) not found for architecture x86_64
clang: error: linker command failed with exit code 1 (use -v to see invocation)
b_defplot.o and other object files were generated when I tried installing plotutils 2.6 by first downloading it, and doing ./configure, make, and make install.
My ultimate goal is to use the libplot package in a program I'm writing that requires a few plots to be generated, and I want my program binary file to be self-contained (i.e. if I execute my program binary on any other computer without plotutils installed, it should still work). This is why I'm linking my binary with every object file that gets created in the libplot folder when I install plotutils as described above.
Any help with the error I'm getting or enlightening me on something I'm doing terribly wrong keeping in mind what my end goal is, would be greatly appreciated.

Answer 1

I managed to compile the libplot example program successfully by following these steps:
Install plotutils via Homebrew using: brew install plotutils
Locate (within /usr/local/ or wherever your Homebrew installation resides) and link libplot.2.2.4.dylibto the C program you are trying to build (in this case, the C program is the one provided in the question).
Also make sure you include the plot.h header file in your header search path.
By following these steps, I was able to compile the above code (with the modifications shown below) cleanly and was able to export the png shown below. Homebrew seems to have saved me the trouble of building plotutils on my own.
I replaced if ((plotter = pl_newpl_r ("ps", stdin, stdout, stderr, plotter_params)) == NULL) with if ((plotter = pl_newpl_r ("png", stdin, fp, stderr, plotter_params)) == NULL) where fp is defined as follows:
FILE *fp;
fp = fopen("/Users/username/path/Test.png", "w");
// rest of example code shown above
fclose(fp);