35 lines
789 B
C
35 lines
789 B
C
#include <stdio.h>
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#include <unistd.h>
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#include <sys/select.h>
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int main(void) {
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fd_set rfds;
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int retval;
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/* Watch stdin (fd 0) to see when it has input. */
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FD_ZERO(&rfds);
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FD_SET(0, &rfds);
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/* timeout 设为 NULL 表示无限等待 */
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retval = select(1, &rfds, NULL, NULL, NULL);
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if (retval == -1) {
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perror("select()");
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} else {
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if (FD_ISSET(0, &rfds)) {
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char buf[256];
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ssize_t n = read(0, buf, sizeof(buf) - 1);
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if (n > 0) {
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buf[n] = '\0';
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printf("Read %zd bytes from stdin: %s", n, buf);
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} else if (n == 0) {
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printf("EOF on stdin\n");
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} else {
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perror("read");
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}
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}
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}
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return 0;
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}
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