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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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