On most Linux systems, the default limit for message queues is 16 which supports only 16 users. The limit can be increased by adding the line "kernel.msgmni = limit" to the text file /etc/sysctl.conf where "limit" is the new limit value. The /etc/sysctl.conf file can be modified using any text editor. For example, adding the line "kernel.msgmni = 72" would set the limit to 72 after the next system reboot. The current limit can be increased by using the command "/sbin/sysctl -w kernel.msgmni=72", but the new value will be lost after the next reboot unless the /etc/sysctl.conf file is modified. The command "ipcs -lq" displays the current message queue limits.