Problem Symptoms: 

Ue_01 stopped with error message 'Glibc detected'. It was not possible to stop the daemon with util e/2 but only by killing it. Now it's not possible to start it again.

And, In another case:

The following is seen in our pc server logs; always after module Z39.50 Services
PROGRAM : pc_z39_c9902
...
*** glibc detected *** .../pc_server_main: malloc(): memory corruption: 0x0a989dc0 ***

In a third case, using util w/3 to start the www_server, though it *did* start, the user got the following message on the screen after the start:

 *** glibc detected *** .../www_server_main: double free or corruption 

,Resolution:

1. Set the following parameter in $alephe_root/aleph_start.private:

    setenv MALLOC_CHECK_ 0   

2. source $alephe_root/aleph_start
3. restart PC server (util w/3/3)
4. Restart the Update Doc Index (util e/1)

Note that there's a space between "MALLOC_CHECK_" and the "0" .

Additional Information

When the parameter MALLOC_CHECK_ 0 parameter is set, a special (less efficient) implementation is used which is designed to be tolerant against simple errors, such as double calls of free() with the same argument, or overruns of a single byte (off-by-one bugs). Not all such errors can be protected against, however, and memory leaks can result.
If MALLOC_CHECK_ is set to 0, any detected heap corruption is silently ignored and an error message is not generated.

See also additional information at Linux manual
man malloc

• Article last edited: 15/March/2016