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#include <common.h>
/**
** User function Q: exit, write, bogus
**
** Reports itself, then tries to execute a bogus system call
**
** Invoked as: userQ x
** where x is the ID character
*/
USERMAIN(main)
{
char ch = 'q'; // default character to print
char buf[128];
// process the command-line arguments
switch (argc) {
case 2:
ch = argv[1][0];
break;
default:
sprint(buf, "userQ: argc %d, args: ", argc);
cwrites(buf);
for (int i = 0; i <= argc; ++i) {
sprint(buf, " %s", argv[argc] ? argv[argc] : "(null)");
cwrites(buf);
}
cwrites("\n");
}
// announce our presence
write(CHAN_SIO, &ch, 1);
// try something weird
bogus();
// should not have come back here!
sprint(buf, "!!!!! %c returned from bogus syscall!?!?!\n", ch);
cwrites(buf);
exit(1);
return (42); // shut the compiler up!
}
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