Increasing the number of pseudo-terminal devices

A pseudo-terminal device is a terminal device that does not have a physical terminal associated with it. When your system is installed, the number of pseudo-terminal devices available for use is configured. It is possible that this number may not be large enough to support your users and/or applications (especially if the default value is used) and this value may need to be increased.

To increase the number of pseudo-terminal devices on your system:

1. Enter the following commands to check the current values of the NUMREGPT and NUMSCOPT parameters:
   
   idtune -g NUMREGPT
   idtune -g NUMSCOPT

   The NUMREGPT parameter specifies the number of regular pseudo-terminals configured The NUMSCOPT parameter specifies the number of SCO OpenServer-compatible pseudo-terminals configured

2. Enter the following command to increase the number of regular pseudo-terminals to num:
   
   idtune -c -f NUMREGPT num

3. If required, enter the following command to increase the number of SCO OpenServer-compatible pseudo-terminals to num:
   
   idtune -c -f NUMSCOPT num

4. If you are changing the number of SCO OpenServer-compatible pseudo-terminals, edit the file /etc/conf/node.d/ptm to define additional master device nodes.

   The contents of this file should be similar to the following:

   clone	ptmx	c	ptm
   ptm	ptyp0	c	32
   ptm	ptyp1	c	33
   .
   .
   .
   ptm	ptyp30	c	62
   ptm	ptyp31	c	63
   

   The first line should be exactly as shown in this example. Subsequent lines are entries for the SCO OpenServer-compatible master nodes. There should be one entry for each device configured above (32 in this example). The device names are ptypn where n increases from 0 NUMSCOPT-1 (31 in this example). The fourth field is the minor number for the device and must be equal to NUMREGPT+n. In the above example, the minor number of ptyp30 is 62 (30+32). If done correctly, the last entry will have a minor number equal to NUMREGPT+NUMSCOPT-1.

5. Edit the file /etc/conf/node.d/pts to change the number of slave device nodes.

   The contents of this file should be similar to the following:

   pts	pts/0	c	0
   pts	pts/1	c	1
   .
   .
   .
   pts	pts/30	c	30
   pts	pts/31	c	31
   pts	ttyp0	c	32
   pts	ttyp1	c	33
   .
   .
   .
   pts	ttyp30	c	62
   pts	ttyp31	c	63
   

   The lines for ``pts/0'' through ``pts/31'' correspond to regular pseudo-terminals. There should be NUMREGPT entries with the device names ranging from ``pts/0'' to ``pts/N'' where N is NUMREGPT-1. The minor numbers also range from 0 to NUMREGPT-1. Subsequent lines for ``ttyp0'' through ``ttyp31'' are for SCO OpenServer-compatible pseudo-terminals. The device names range from ttyp0 to ttypN where N is NUMSCOPT-1. As with the master nodes, the minor number associated with ``ttyp0'' should equal NUMREGPT and increase by 1 for each subsequent entry. When done, this file should have NUMREGPT+NUMSCOPT entries, and the last minor number defined should have the value NUMREGPT+NUMSCOPT-1.

6. Enter the following command to rebuild the kernel:
   
   idbuild -K

7. Enter the following command to reboot:
   
   init 6