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#include <common.h>
/**
** User function main #5: exit, fork, exec, write
**
** Iterates spawning copies of userW (and possibly userZ), reporting
** their PIDs as it goes.
**
** Invoked as: main5 x n b
** where x is the ID character
** n is the iteration count
** b is the w&z boolean
*/
USERMAIN( main ) {
int count = 5; // default iteration count
char ch = '5'; // default character to print
int alsoZ = 0; // also do userZ?
char msgw[] = "*5w*";
char msgz[] = "*5z*";
char buf[128];
// process the command-line arguments
switch( argc ) {
case 4: alsoZ = argv[3][0] == 't';
// FALL THROUGH
case 3: count = str2int( argv[2], 10 );
// FALL THROUGH
case 2: ch = argv[1][0];
break;
default:
sprint( buf, "main5: 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" );
}
// update the extra message strings
msgw[1] = msgz[1] = ch;
// announce our presence
write( CHAN_SIO, &ch, 1 );
// set up the argument vector(s)
// W: 15 iterations, 5-second sleep
char *argsw[] = { "userW", "W", "15", "5", NULL };
// Z: 15 iterations
char *argsz[] = { "userZ", "Z", "15", NULL };
for( int i = 0; i < count; ++i ) {
write( CHAN_SIO, &ch, 1 );
int whom = spawn( ProgW, argsw );
if( whom < 1 ) {
swrites( msgw );
}
if( alsoZ ) {
whom = spawn( ProgZ, argsz );
if( whom < 1 ) {
swrites( msgz );
}
}
}
exit( 0 );
return( 42 ); // shut the compiler up!
}
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