38 lines
828 B
C
38 lines
828 B
C
#include <sys/types.h>
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#include <sys/stat.h>
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#include <fcntl.h>
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#include <string.h>
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#include <unistd.h>
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#include <stdio.h>
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int main(int argc, char const *argv[])
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{
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int fd;
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char status = 0;
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if (argc != 3) {
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printf("Usage: %s <dev> <on|off>\r\n", argv[0]);
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printf(" eg: %s /dev/led0 on\r\n", argv[0]);
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printf(" eg: %s /dev/led0 off\r\n", argv[0]);
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return -1;
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}
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fd = open(argv[1], O_RDWR);
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if (fd < 0) {
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printf("Cannot open %s\r\n", argv[1]);
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return -1;
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}
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if (strcmp(argv[2], "on") == 0) {
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status = 1;
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} else if (strcmp(argv[2], "off") == 0) {
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status = 0;
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} else {
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printf("Invalid argument: %s\r\n", argv[2]);
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close(fd);
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return -1;
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}
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write(fd, &status, 1);
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close(fd);
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return 0;
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}
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