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#include <common.h>
/**
** User function Z: exit, sleep, write, getpid
**
** Prints its ID, then records PID and PPID, loops printing its ID,
** and finally re-gets PPID for comparison. Yields after every second
** ID print in the loop.
**
** This code is used as a handy "spawn me" test routine; it is spawned
** by several of the standard test processes.
**
** Invoked as: userZ x [ n ]
** where x is the ID character
** n is the iteration count (defaults to 10)
*/
USERMAIN(main)
{
int count = 10; // default iteration count
char ch = 'z'; // default character to print
char buf[128];
// 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, "?: 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
int pid = getpid();
sprint(buf, " %c[%d]", ch, pid);
swrites(buf);
// iterate for a while; occasionally yield the CPU
for (int i = 0; i < count; ++i) {
sprint(buf, " %c[%d]", ch, i);
swrites(buf);
DELAY(STD);
if (i & 1) {
sleep(0);
}
}
exit(0);
return (42); // shut the compiler up!
}
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