Maximum files per session

The number of file handles for an OS/2 session is limited to n (where n 
depends on the OS/2 version you're using, normally n is 20; or 40 in WARP 
4). So you can only open about n-5 files at one time, because 5 handles 
are already used by the standard input and output channels (STDIN, STDOUT, 
STDERR, ...). 

To check or increase this value you may use a tool like MaxFH, 
<SysAddFileHandle (in the REXXUTIL.DLL from Object-Oriented REXX), or 
similar functions in packages like RXU. 

Beginning with WARP 4 Fixpack #6 you can add the statement 

 
  SET SHELLHANDLESINC=n

to your CONFIG.SYS to increase the default numbers of free file handles by 
n for every shell process (see CONFIG.SYS statements used by OS/2) 

Note:  There seems to be no file handle limit for Object-Oriented REXX. 

 Note:  see also It runs, runs not, runs, runs not, ...