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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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