The (C style) description of a tar record.

/*

      Standard Archive Format - Standard TAR - USTAR

     #define  RECORDSIZE  512
     #define  NAMSIZ      100
     #define  TUNMLEN      32
     #define  TGNMLEN      32

     union record {
         char        charptr[RECORDSIZE];
         struct header {
             char    name[NAMSIZ];
             char    mode[8];
             char    uid[8];
             char    gid[8];
             char    size[12];
             char    mtime[12];
             char    chksum[8];
             char    linkflag;
             char    linkname[NAMSIZ];
             char    magic[8];
             char    uname[TUNMLEN];
             char    gname[TGNMLEN];
             char    devmajor[8];
             char    devminor[8];
         } header;
     };

*/