HP-UX Reference (11i v2 07/12) - 3 Library Functions A-M (vol 6)
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getutx(3C) getutx(3C)
setutxent() Resets the input stream to the beginning of the file. This should be done before each
search for a new entry if it is desired that the entire file be examined.
endutxent() Closes the currently open file.
The most current entry is saved in a static structure. Multiple accesses require that the structure be copied
before further accesses are made. During each call to either
getutxid() or getutxline() , the
static structure is examined before performing more
I/O. If the contents of the static structure match what
the routine is searching for, no additional searching is done. Therefore, if using
getutxline() to
search for multiple occurrences, it is necessary to zero out the static structure after each success; otherwise
getutxline() simply returns the same pointer over and over again. There is one exception to the rule
about removing the structure before a new read: The implicit read done by
pututxline() (if it finds
that it is not already at the correct place in the file) does not alter the contents of the static structure
returned by
getutxent() , getutxid() ,or getutxline()
if the user has just modified those con-
tents and passed the pointer back to
pututxline()
.
RETURN VALUE
These functions return a
NULL pointer upon failure to read (whether for permissions or having reached
end-of-file), or upon failure to write. They also return a
NULL pointer if the size of the file is not an integral
multiple of
sizeof(struct utmpx)
.
If
pututxline() is successful, it returns a pointer to a static location containing the most current
utmpx entry. The contents of this structure are identical to the contents of the supplied utmpx structure
if successful. If
pututline() fails upon writing to utmpx, it returns a NULL pointer. If putu-
line()
is successful in writing to the utmpx file but fails in writing to the
utmp file, then putut-
line()
will behave as if it succeeded. Note that the utmpx file and the utmp
file may not be in sync
due to the above behavior.
pututxline() is only guaranteed to have written to the utmpx file upon
successful completion.
FILES
/etc/utmp
/etc/utmpx
/var/adm/wtmp
SEE ALSO
getut(3C), getutent(3C), ttyslot(3C), utmp(4), thread_safety(5).
STANDARDS CONFORMANCE
endutxent() :XPG4.2
getutxent() :XPG4.2
getutxid() :XPG4.2
getutxline() :XPG4.2
pututxline() :XPG4.2
setutxent() :XPG4.2
HP-UX 11i Version 2: December 2007 Update − 2 − Hewlett-Packard Company 561