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 NAME     
 |  |  |  | udpread, udpwrite – read and write UDP packets 
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 SYNOPSIS     
 |  |  |  | #include <u.h> 
    
    
    #include <libc.h> 
    
    
    #include <ip.h> 
    
    
    typedef struct Udphdr Udphdr; struct Udphdr
 {
 
 };|  |  |  | uchar    raddr[IPaddrlen];/* remote address and port */ uchar    laddr[IPaddrlen];/* local address and port */
 uchar    rport[2];
 uchar    lport[2];
 
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 long       udpread(int fd, Udphdr *hdr, void *data, long n)
 long udpwrite(int fd, Udphdr *hdr, void *data, long n)
 
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 DESCRIPTION     
 |  |  |  | Udpread and udpwrite read and write UDP packets from the UDP network
    connection established on file descriptor fd. 
    
    
    Udpread reads at most n bytes of packet body into data , stores
    the header in hdr, and returns the number of bytes stored in data.
    
    
    
    Udpwrite writes the n bytes stored in data in a UDP packet with
    header hdr. 
    
    
    Note that the Udphdr frames the addresses as local and remote
    instead of source and destination. Thus the hdr filled in for
    a packet read by udpread can be used unchanged in udpwrite to
    send a response back to the sender of the original packet. 
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 SOURCE     
 SEE ALSO    
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