EDT PCIe Gen1 Framegrabbers, Руководство пользователя

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Camera Link PCI Express (PCIe) Gen1 Framegrabbers Appendix D: VxWorks
EDT, Inc. 2012 March 16 37
#else
int main(int argc, char **argv)
#endif
{
#ifdef NO_MAIN
char **argv = 0 ;
int argc = 0 ;
opt_create_argv("xtest",command_line,&argc,&argv);
#endif
The rest of the code in the
xtest.c
file deals with
argv
and
argc
and works the same on VxWorks as
on other operating systems.
Note also these other portability issues:
• Stack size is set by the user; it does not grow automatically as it would in other operating systems.
• To prevent namespace conflicts, application functions should be declared static.
• Global variables should not be used; if they are used, declare them static.
Any globals and statics will have correct values only the first time the program is run; after that, the variables
are still present and if nothing resets them, problems will occur when the program runs again.
Example: If global
init_done = 0
and
my_prog()
sets the global
init_done = 1,
then next time the
program is run,
init_done
will be 1. Thus,
my_prog()
should reset
init_done = 0
right before exit.