exec() weirdness!!

ronman

Hi,
dot (an graph renderer from graphviz) works perfectly being called from within PHP:

exec("dot output/grade4/brainstormgraph.dot -o output/grade4/graph.gxl");

but the exact same line with a different executable outputs an empty file, EVEN THOUGH the two executables are in the same directory and have the same permissions.

exec("dot2gxl output/grade4/brainstormgraph.dot -o output/grade4/graph.gxl");

(graph.gxl is generated, but zero length)

however, if I copy/paste the same command to a command line:

ronman$ dot2gxl output/grade4/brainstormgraph.dot -o output/grade4/graph.gxl

it works perfectly.

No error messages in the PHP log. I tried other PHP execution functions, like system() and the backtick operator with the same result. I thought it might be a permissions problem, but dot and dot2gxl are in the same directory and have the same permissions.

My sys admin suggested using full paths for all filenames but this doesn't work, either.

We're running on Linux RedHat 7.3.

Thanks in advance,
Ron

HalfaBee

Try
system( 'command' , $return_error );
echo $return_error;

To see if an error is occuring.

HalfaBee