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PORuby C extension rb_str_new2 seems to return false
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copied!<p>I cannot post my actual code due to work copyright, so I will try to show my problem with simple example code.</p> <p>I have a C extension whose simplified version looks like:</p> <pre><code>#include <ruby.h> #include <termios.h> #include <stdio.h> #include <fcntl.h> #include <unistd.h> #include <errno.h> #include <string.h> VALUE test(VALUE self, VALUE string); void Init_module_name() { module_name = rb_define_module("Modulename"); c_modulename = rb_define_class_under(modulename, "Class", rb_cObject); rb_define_method(c_modulename, "test", test, 1); e_ModuleNameError = rb_define_class_under(modulename, "Error", rb_eStandardError); } VALUE test(VALUE self, VALUE string) { char *c_string = StringValueCStr(string); int fd = open(c_string, O_RDWR | O_NOCTTY | O_NONBLOCK); if (fd == -1) { rb_raise(e_ModuleNameError, "Failed to open file"); } if (!isatty(fd)) { rb_raise(e_ModuleNameError, "File is not a tty"); } struct termios config; int termios_ret = init_termios(config, fd) if (termios_ret != OK) { // OK defined by enum in modulename's header close(fd); rb_raise(e_ModuleNameError, "Termios init failed."); } int success = write(fd, "I'm a string", str_length); if (success < str_length) { close(fd); rb_raise(e_ModuleNameError, "Failed to write to file."); } close(fd); return rb_str_new2("Success"); } </code></pre> <p>Then, the ruby code that requires this looks like:</p> <pre><code>require 'modulename' class ModuleName attr_acessor :file def initialize(file) @file = file @object = Modulename::Class.new end def test @object.test @file end end </code></pre> <p>Which is then called in my production project like:</p> <pre><code>require "modulename_ruby_file" x = ModuleName "/dev/pts/1" x.test </code></pre> <p>Here is the interesting thing. When I run this code in production, the return value from x.test above is false (As in literally the value false, not a string). Also, the write to the file never happens. However, if I do it in some simplified test code it returns the string "Success" just like expected and the write is indeed completed.</p> <p>Does anyone know of any situation that would cause this function not to execute the write, and return false? I already tried putting a rescue around it in case it was throwing one of the rb_raises, but it doesn't appear to be.</p> <p>Me and 3 other members of my team have looked at this all afternoon and have not found an answer.</p>

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