You can use the
uname function to find out some information about
the type of computer your program is running on. This function and the
associated data type are declared in the header file
As a bonus,
uname also gives some information identifying the
particular system your program is running on. This is the same information
which you can get with functions targetted to this purpose described in
utsnamestructure is used to hold information returned by the
unamefunction. It has the following members:
- This is the name of the operating system in use.
- This is the current release level of the operating system implementation.
- This is the current version level within the release of the operating system.
- This is a description of the type of hardware that is in use.
Some systems provide a mechanism to interrogate the kernel directly for this information. On systems without such a mechanism, the GNU C Library fills in this field based on the configuration name that was specified when building and installing the library.
GNU uses a three-part name to describe a system configuration; the three parts are cpu, manufacturer and system-type, and they are separated with dashes. Any possible combination of three names is potentially meaningful, but most such combinations are meaningless in practice and even the meaningful ones are not necessarily supported by any particular GNU program.
Since the value in
machineis supposed to describe just the hardware, it consists of the first two parts of the configuration name: ‘cpu-manufacturer’. For example, it might be one of these:
- This is the host name of this particular computer. In the GNU C Library, the value is the same as that returned by
gethostname; see Host Identification.
gethostname() is implemented with a call to uname().
- This is the NIS or YP domain name. It is the same value returned by
getdomainname; see Host Identification. This element is a relatively recent invention and use of it is not as portable as use of the rest of the structure.
unamefunction fills in the structure pointed to by info with information about the operating system and host machine. A non-negative value indicates that the data was successfully stored.
-1as the value indicates an error. The only error possible is
EFAULT, which we normally don't mention as it is always a possibility.