senderr.c

unix环境高级编程的源代码

#include    "ourhdr.h"

/* Used when we had planned to send an fd using send_fd(),
 * but encountered an error instead.  We send the error back
 * using the send_fd()/recv_fd() protocol. */

int
send_err(int clifd, int errcode, const char *msg)
{
    int        n;

    if ( (n = strlen(msg)) > 0)
        if (writen(clifd, msg, n) != n)    /* send the error message */
            return(-1);

    if (errcode >= 0)
        errcode = -1;    /* must be negative */

    if (send_fd(clifd, errcode) < 0)
        return(-1);

    return(0);
}