|ENDGRENT(3P)||POSIX Programmer's Manual||ENDGRENT(3P)|
void endgrent(void); struct group *getgrent(void); void setgrent(void);
An implementation that provides extended security controls may impose further implementation-defined restrictions on accessing the group database. In particular, the system may deny the existence of some or all of the group database entries associated with groups other than those groups associated with the caller and may omit users other than the caller from the list of members of groups in database entries that are returned.
The setgrent() function shall rewind the group database so that the next getgrent() call returns the first entry, allowing repeated searches.
The endgrent() function shall close the group database.
The setgrent() and endgrent() functions shall not change the setting of errno if successful.
On error, the setgrent() and endgrent() functions shall set errno to indicate the error.
Since no value is returned by the setgrent() and endgrent() functions, an application wishing to check for error situations should set errno to 0, then call the function, then check errno.
These functions need not be thread-safe.
The application shall not modify the structure to which the return value points, nor any storage areas pointed to by pointers within the structure. The returned pointer, and pointers within the structure, might be invalidated or the structure or the storage areas might be overwritten by a subsequent call to getgrgid(), getgrnam(), or getgrent(). The returned pointer, and pointers within the structure, might also be invalidated if the calling thread is terminated.
- A signal was caught during the operation.
- An I/O error has occurred.
In addition, the getgrent() and setgrent() functions may fail if:
- All file descriptors available to the process are currently open.
- The maximum allowable number of files is currently open in the system.
The following sections are informative.
The Base Definitions volume of POSIX.1‐2017, <grp.h>
Any typographical or formatting errors that appear in this page are most likely to have been introduced during the conversion of the source files to man page format. To report such errors, see https://www.kernel.org/doc/man-pages/reporting_bugs.html .
|2017||IEEE/The Open Group|