getgid()--Get Real Group ID

 #include <unistd.h>

 gid_t getgid(void);  

The getgid() function returns the real group ID (GID) of the calling thread. The real GID is the group ID under which the thread was created.

Note:: When a user profile swap is done with the QWTSETP API prior to running the getgid() function, the GID for the current profile is returned.

Parameters

None.

Authorities

No authorization is required.

Return Value

> 0

getgid() was successful. The value returned represents the GID.

>= 0

getgid() was successful. If there is no GID, the user ID has no group profile associated with it and returns 0. Otherwise, if there is a group profile, the API returns the GID of the group profile.

-1

getgid() was not successful. The errno global variable is set to indicate the error.

Error Conditions

If getgid() is not successful, errno usually indicates one of the following errors. Under some conditions, errno could indicate an error other than those listed here.

Related Information

• The <unistd.h> file (see Header Files for UNIX-Type Functions)

Example

See Code disclaimer information for information pertaining to code examples.

The following example gets the real GID.

#include <unistd.h>

main()
{
  gid_t gid;

  if (-1 == (gid = getgid(void)))
     perror("getgid() error.");
  else
     printf("The real GID is: %u\n", gid);

}

Output:

  The real GID is: 75