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#include <common.h>
/**
** User function J: exit, fork, exec, write
**
** Reports, tries to spawn lots of children, then exits
**
** Invoked as: userJ x [ n ]
** where x is the ID character
** n is the number of children to spawn (defaults to 2 * N_PROCS)
*/
USERMAIN(main)
{
int count = 2 * N_PROCS; // number of children to spawn
char ch = 'j'; // 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, "userJ: 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);
// set up the command-line arguments
char *argsy[] = { "userY", "Y", "10", NULL };
for (int i = 0; i < count; ++i) {
int whom = spawn(ProgY, argsy);
if (whom < 0) {
write(CHAN_SIO, "!j!", 3);
} else {
write(CHAN_SIO, &ch, 1);
}
}
exit(0);
return (42); // shut the compiler up!
}
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