39 lines
653 B
C++
39 lines
653 B
C++
#include <ctype.h>
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#include <stdio.h>
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#include <string.h>
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#include <unistd.h>
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int usage(char* argv0, int ret)
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{
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FILE* fp = (ret == 0) ? stdout : stderr;
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fprintf(fp, "usage: %s SECONDS\n", argv0);
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return ret;
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}
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int main(int argc, char** argv)
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{
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if (argc != 2)
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return usage(argv[0], 1);
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if (strlen(argv[1]) > 9)
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{
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fprintf(stderr, "SECONDS argument too large\n");
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return usage(argv[0], 1);
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}
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int seconds = 0;
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const char* ptr = argv[1];
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while (*ptr)
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{
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if (!isdigit(*ptr))
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{
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fprintf(stderr, "invalid SECONDS argument\n");
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return usage(argv[0], 1);
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}
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seconds = (seconds * 10) + (*ptr - '0');
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ptr++;
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}
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sleep(seconds);
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}
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