gistfile1.d

import std.c.string;
import std.conv;

string formatError(int err, string prefix = "") {
    version(Posix) {
        char[512] buf;
        const(char)* cs;

        version (linux) {
            cs = strerror_r(err, buf.ptr, buf.length);
        }
        else version (OSX) {
            auto errs = strerror_r(err, buf.ptr, buf.length);
            if (errs == 0) {
                cs = buf.ptr;
            }
            else {
                return prefix ~ to!string(err);
            }
        }
        else version (FreeBSD) {
            auto errs = strerror_r(err, buf.ptr, buf.length);

            if (errs == 0) {
                cs = buf.ptr;
            }
            else {
                return prefix ~ to!string(err);
            }
        }
        else {
            static assert(0);
        }

        auto len = strlen(cs);

        if(cs[len - 1] == '\n') {
            len--;
        }

        if(cs[len - 1] == '\r') {
            len--;
        }

        return cs[0 .. len].idup;
    }
    else version(Windows) {
        import std.windows.syserror;

        try {
            return prefix ~ sysErrorString(err);
        } catch (Exception e) {
            return prefix ~ "error " ~ to!string(err);
        }
    }
    else {
        return prefix ~ to!string(err);
    }
}