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#include <common.h>
/**
** User function main #4: exit, fork, exec, sleep, write
**
** Loops, spawning N copies of userX and sleeping between spawns.
**
** Invoked as: main4 x n
** where x is the ID character
** n is the iteration count (defaults to 5)
*/
USERMAIN(main)
{
int count = 5; // default iteration count
char ch = '4'; // default character to print
int nap = 30; // nap time
char msg2[] = "*4*"; // "error" message to print
char buf[32];
// process the command-line arguments
switch (argc) {
case 3:
count = str2int(argv[2], 10);
// FALL THROUGH
case 2:
ch = argv[1][0];
break;
default:
sprint(buf, "main4: 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);
// argument vector for the processes we will spawn
char *arglist[] = { "userX", "X", buf, NULL };
for (int i = 0; i < count; ++i) {
write(CHAN_SIO, &ch, 1);
// second argument to X is 100 plus the iteration number
sprint(buf, "%d", 100 + i);
int whom = spawn(ProgX, arglist);
if (whom < 0) {
swrites(msg2);
} else {
write(CHAN_SIO, &ch, 1);
}
sleep(SEC_TO_MS(nap));
}
exit(0);
return (42); // shut the compiler up!
}
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