When you're trying to determine your system's limits, you can get the values of configurable limits, special read-only variables that store system information.
You can use the POSIX getconf utility to get the value of a configurable limit or a configuration string. Since getconf is a POSIX utility, scripts that use it instead of hard-coded QNX-specific limits can adapt to other POSIX environments.
Some configurable limits are associated with a path; their names start with _PC_. When you get the value of these limits, you must provide the path (see Filesystem limits , below). For example, to get the maximum length of the filename, type:
getconf _PC_NAME_MAX pathname
Other limits are associated with the entire system; their names start with _SC_. You don't have to provide a path when you get their values. For example, to get the maximum number of files that a process can have open, type:
In general, you can't change the value of the configurable limits — they're called configurable because the system can set them.
The BlackBerry PlayBook OS libraries provide various functions that you can use in a program to work with configurable limits:
- Get the value of a configurable limit that's associated with a path.
- Get the value of a limit for the entire system.
- Change the value of certain limits. For example, you can use this function to limit the number of files that a process can open; this limit also depends on the value of the -F option to procnto .