TID100643 (RDCMPFE) - FEsopen() fails to read compressed files

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ABSTRACT:

FEsopen() returns -1 when ENABLE_IO_ON_COMPRESSED_DATA_BIT flag bit is used .

DETAILED DESCRIPTION

Customer wanted to do compressed file I/O with the following call

fh=FEsopen("SYS:MYFILE", O_RDWR, SH_COMPAT,0, ENABLE_IO_ON_COMPRESSED_DATA_BIT | LEAVE_FILE_COMPRESSED_DATA_BIT, PrimaryDataStream);

FEsopen() returned always -1, errno = 6 and NetWareErrno = 144. If the ENABLE_IO_ON_COMPRESSED_DATA_BIT flag was removed the call succeeded, but obviously getting uncompressed data.

Solution: to open for compressed I/O the file has to be opened in "exclusive mode" so use SH_DENYRW mode instead of SH_COMPAT. if you are simply reading from the file you probably want to have an access mode of O_RDONLY or O_WRONLY if writing it.

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