I cannot read the last 4-byte word in a file using lseek + read:
/* file "foo" exists and is large enough - say, 4 MB */
int fd = open("foo",O_RDONLY|O_BINARY);
uint32 data;
/* this succeeds and correctly returns the size of file "foo" minus 4 */
lseek(fd,-sizeof(data),SEEK_END);
/* this returns 0 -- instead of the expected 4 -- and sets errno to ENOENT */
read(fd,&data,sizeof(data));
if I run this under gdb and type
lseek(fd,-sizeof(data),SEEK_END);
read(fd,&data,sizeof(data));
several times, eventually read() starts to return 4 and set data to the
value I actually wrote into "foo" last.
I observe this on linux, cygwin and solaris -- what am I doing wrong?
Thanks!
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