68 lines
1.5 KiB
C
68 lines
1.5 KiB
C
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#include <stdlib.h>
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#include <stdio.h>
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#include <signal.h>
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#include <sys/types.h>
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#include <sys/stat.h>
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#include <string.h>
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#include <fcntl.h>
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void syserr( const char *msg ) {
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perror(msg);
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exit(EXIT_FAILURE);
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}
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main()
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{
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int rfd, wfd;
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char buff[64096];
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int nb;
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int ed;
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remove("duck");
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if( mkfifo( "duck", 0666 ) == -1 ) {
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syserr( "mkfifo" );
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}
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switch( fork() ) {
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case -1: syserr("fork" ); break;
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case 0: // child
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printf( "Child awakes\n" );
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if( (rfd = open( "duck", O_RDWR )) == -1 ) {
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syserr( "open for reading" );
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}
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printf("Child: open completes\n");
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for( ; ; ) {
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if( (nb = read( rfd, buff, 200 )) == -1 ) {
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syserr( "read" );
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}
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if( nb == 0 ) {
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printf("No more data\n");
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printf("child terminates 0\n");
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exit( 0 );
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}
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buff[nb] = '\0';
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printf("nb = %d Buff = |%s|\n", nb, buff);
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}
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break;
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default: // parent
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printf( "Parent awake\n" );
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if( (wfd = open( "duck", O_RDWR )) == -1 ) {
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syserr( "open for writing" );
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}
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printf("Parent opened pipe to write\n");
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for( ed = 0; ed < 4; ed++ ) {
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sprintf( buff, "duckie %d", ed + 1 );
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if(write( wfd, buff, strlen(buff)) != strlen(buff)) {
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syserr( "write" );
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}
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}
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printf("parent terminates\n");
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close(wfd);
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remove("duck");
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sleep(1);
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}
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}
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