You can't: because of he algorithm used there is no direct relation between the source and the target file size: if file X is bigger than file Y then X.gz might still be smaller than Y.gz. The only...
After the tar has finished you can consult the exit code (=errorlevel). As always in Unix, "0" means no error, any other code means various sorts of error conditions. Check the man page for further...
AIX adheres to the "USTAR" standard (http://en.wikipedia.org/wiki/Tar_%28computing%29). The 2GB limit was lifted with AIX 5.1, as shockneck pointed out (https://www.unix.com/302236185-post2.html). AIX...