diff --git a/util.c b/util.c index 46bc89d..34fd789 100644 --- a/util.c +++ b/util.c @@ -139,9 +139,29 @@ read_buffer (fd, buf, cnt) voidp buf; unsigned int cnt; { + int len; +#ifdef INT_MAX if (INT_MAX < cnt) cnt = INT_MAX; - return read (fd, buf, cnt); +#endif + len = read (fd, buf, cnt); + +#if defined F_SETFL && O_NONBLOCK && defined EAGAIN + /* Iput files are opened O_NONBLOCK for security reasons. On some + file systems this can cause read to fail with errno == EAGAIN. */ + if (len < 0 && errno == EAGAIN) + { + int flags = fcntl (fd, F_GETFL); + if (0 <= flags) + { + if (! (flags & O_NONBLOCK)) + errno = EAGAIN; + else if (fcntl (fd, F_SETFL, flags & ~O_NONBLOCK) != -1) + len = read (fd, buf, cnt); + } + } +#endif + return len; } /* Likewise for 'write'. */