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// Copyright Yahoo. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
#include <cstdio>
#include <cerrno>
#include <cstring>
#include <fcntl.h>
#include <unistd.h>
#include <system_error>
int main(int argc, char **argv) {
if (argc != 2) {
fprintf(stderr, "%s <filename>\n", argv[0]);
return 1;
}
const char *fileName = argv[1];
int fh = open(fileName, O_RDONLY);
if (fh == -1) {
std::error_code ec(errno, std::system_category());
fprintf(stderr, "Failed opening file %s: %s\n", fileName, ec.message().c_str());
return 2;
}
int retval = 0;
#ifdef __linux__
int err = posix_fadvise(fh, 0, 0, POSIX_FADV_DONTNEED);
if (err != 0) {
std::error_code ec(errno, std::system_category());
fprintf(stderr, "posix_fadvise failed: %s\n", ec.message().c_str());
retval = 3;
}
#endif
close(fh);
return retval;
}
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