67 lines
1.2 KiB
C
67 lines
1.2 KiB
C
/*
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* SPDX-License-Identifier: MIT
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* Copyright (c) 2025 Fabio Scotto di Santolo
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*/
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#include <stdio.h>
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#include <sys/time.h>
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#include <sys/types.h>
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#include <unistd.h>
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#define TIMEOUT 5
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#define BUF_LEN 1024
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int main(void)
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{
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struct timeval tv;
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fd_set readfds;
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int ret;
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/* Wait on stdin for intput. */
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FD_ZERO(&readfds);
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FD_SET(STDIN_FILENO, &readfds);
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/* Wait up to file seconds */
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tv.tv_sec = TIMEOUT;
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tv.tv_usec = 0;
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/* All right, now block! */
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ret = select(STDIN_FILENO + 1, &readfds, NULL, NULL, &tv);
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if (ret == -1) {
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perror("select");
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return 1;
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} else if (!ret) {
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printf("%d seconds elapsed.\n", TIMEOUT);
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return 0;
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}
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/*
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* Is our file descriptor ready to read?
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* (It must be, as it was the only fd that
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* we provided and the call returned
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* nonzero, but we will humor ourselves.)
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*/
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if (FD_ISSET(STDIN_FILENO, &readfds)) {
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char buf[BUF_LEN + 1];
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int len;
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/* guaranteed to not block */
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len = read(STDIN_FILENO, buf, BUF_LEN);
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if (len == -1) {
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perror("read");
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return 1;
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}
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if (len) {
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buf[len] = '\0';
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printf("read: %s\n", buf);
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}
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return 0;
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}
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fprintf(stderr, "This should not happen!\n");
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return 1;
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}
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