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#include <sys/types.h>
#include <sys/time.h>
#include <stdio.h>
main()
{
int n, nfds;
char buf[32];
fd_set readfds;
struct timeval tv;
/*
* We will be reading from standard input (file
* descriptor 0), so we want to know when the
* user has typed something.
*/
FD_ZERO(&readfds);
FD_SET(0, &readfds);
/*
* Set the timeout for 15 seconds.
*/
tv.tv_sec = 15;
tv.tv_usec = 0;
/*
* Prompt for input.
*/
printf("Type a word; if you don't in 15 ");
printf("seconds I'll use \"WORD\": ");
fflush(stdout);
/*
* Now call select. We pass NULL for
* writefds and exceptfds, since we
* aren't interested in them.
*/
nfds = select(1, &readfds, NULL, NULL, &tv);
/*
* Now we check the results. If nfds is zero,
* then we timed out, and should assume the
* default. Otherwise, if file descriptor 0
* is set in readfds, that means that it is
* ready to be read, and we can read something
* from it.
*/
if (nfds == 0) {
strcpy(buf, "WORD");
}
else {
if (FD_ISSET(0, &readfds)) {
n = read(0, buf, sizeof(buf));
buf[n-1] = '\0';
}
}
printf("\nThe word is: %s\n", buf);
exit(0);
}
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