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Author | SHA1 | Date |
---|---|---|
Michael Kerrisk | c2d505de65 | |
Michael Kerrisk | eb0ea88505 | |
Michael Kerrisk | ef0350ce4c | |
Michael Kerrisk | 1875f17753 | |
Alejandro Colomar | 4e7bd2d06b | |
Peter Collingbourne | 7dd4af5158 | |
Michael Kerrisk | 9b6cce9936 | |
Alejandro Colomar | 06501029e1 | |
Michael Kerrisk | 5e833e276d | |
Michael Kerrisk | e6b7a7b823 | |
Alejandro Colomar | c6d8334b58 | |
James O. D. Hunt | 87ce949275 | |
Alejandro Colomar | 71a62d6c3c | |
Michael Kerrisk | c8219af767 | |
Michael Kerrisk | 5d9f0bc6c5 | |
Pali Rohár | 572422a678 | |
Pali Rohár | aad1f0e890 | |
Pali Rohár | 95dedaa061 | |
Michael Kerrisk | d192b1c7b4 | |
Pali Rohár | 19ddd96b52 | |
Alejandro Colomar | a53fba5e42 | |
Pali Rohár | 4e972a7c84 | |
Pali Rohár | 69452aadaf | |
Pali Rohár | b9a8ee5a97 | |
Štěpán Němec | dbba2b268b | |
наб | dc2c64be7a | |
G. Branden Robinson | c99dbb2776 | |
Michael Weiß | 1b8089e1d1 | |
Michael Kerrisk | 9b94b63df5 |
|
@ -23,14 +23,11 @@ ldd \- print shared object dependencies
|
||||||
prints the shared objects (shared libraries) required by each program or
|
prints the shared objects (shared libraries) required by each program or
|
||||||
shared object specified on the command line.
|
shared object specified on the command line.
|
||||||
An example of its use and output
|
An example of its use and output
|
||||||
(using
|
|
||||||
.BR sed (1)
|
|
||||||
to trim leading white space for readability in this page)
|
|
||||||
is the following:
|
is the following:
|
||||||
.PP
|
.PP
|
||||||
.in +4n
|
.in +4n
|
||||||
.EX
|
.EX
|
||||||
$ \fBldd /bin/ls | sed \(aqs/^ */ /\(aq\fP
|
$ \fBldd /bin/ls\fP
|
||||||
linux\-vdso.so.1 (0x00007ffcc3563000)
|
linux\-vdso.so.1 (0x00007ffcc3563000)
|
||||||
libselinux.so.1 => /lib64/libselinux.so.1 (0x00007f87e5459000)
|
libselinux.so.1 => /lib64/libselinux.so.1 (0x00007f87e5459000)
|
||||||
libcap.so.2 => /lib64/libcap.so.2 (0x00007f87e5254000)
|
libcap.so.2 => /lib64/libcap.so.2 (0x00007f87e5254000)
|
||||||
|
|
|
@ -245,7 +245,8 @@ and
|
||||||
.IR intcurrsym .
|
.IR intcurrsym .
|
||||||
.TP
|
.TP
|
||||||
.B \-\-posix
|
.B \-\-posix
|
||||||
Conform strictly to POSIX. Implies
|
Conform strictly to POSIX.
|
||||||
|
Implies
|
||||||
.BR \-\-verbose .
|
.BR \-\-verbose .
|
||||||
This option currently has no other effect.
|
This option currently has no other effect.
|
||||||
POSIX conformance is assumed if the environment variable
|
POSIX conformance is assumed if the environment variable
|
||||||
|
|
|
@ -358,8 +358,8 @@ call will still fail.
|
||||||
These calls
|
These calls
|
||||||
may not work correctly on NFSv2 filesystems with UID mapping enabled,
|
may not work correctly on NFSv2 filesystems with UID mapping enabled,
|
||||||
because UID mapping is done on the server and hidden from the client,
|
because UID mapping is done on the server and hidden from the client,
|
||||||
which checks permissions. (NFS versions 3 and higher perform the check on
|
which checks permissions.
|
||||||
the server.)
|
(NFS versions 3 and higher perform the check on the server.)
|
||||||
Similar problems can occur to FUSE mounts.
|
Similar problems can occur to FUSE mounts.
|
||||||
.\"
|
.\"
|
||||||
.\"
|
.\"
|
||||||
|
|
|
@ -33,9 +33,6 @@ close_range \- close all file descriptors in a given range
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||||||
.BI "int close_range(unsigned int " first ", unsigned int " last ,
|
.BI "int close_range(unsigned int " first ", unsigned int " last ,
|
||||||
.BI " unsigned int " flags );
|
.BI " unsigned int " flags );
|
||||||
.fi
|
.fi
|
||||||
.PP
|
|
||||||
.IR Note :
|
|
||||||
There is no glibc wrapper for this system call; see NOTES.
|
|
||||||
.SH DESCRIPTION
|
.SH DESCRIPTION
|
||||||
The
|
The
|
||||||
.BR close_range ()
|
.BR close_range ()
|
||||||
|
@ -100,8 +97,6 @@ Library support was added in glibc in version 2.34.
|
||||||
.BR close_range ()
|
.BR close_range ()
|
||||||
is a nonstandard function that is also present on FreeBSD.
|
is a nonstandard function that is also present on FreeBSD.
|
||||||
.SH NOTES
|
.SH NOTES
|
||||||
Glibc does not provide a wrapper for this system call; call it using
|
|
||||||
.BR syscall (2).
|
|
||||||
.SS Closing all open file descriptors
|
.SS Closing all open file descriptors
|
||||||
.\" 278a5fbaed89dacd04e9d052f4594ffd0e0585de
|
.\" 278a5fbaed89dacd04e9d052f4594ffd0e0585de
|
||||||
To avoid blindly closing file descriptors
|
To avoid blindly closing file descriptors
|
||||||
|
|
|
@ -685,7 +685,8 @@ These are legal only for the superuser or the owner of the current terminal.
|
||||||
.TP
|
.TP
|
||||||
.B "TIOCLINUX, subcode=0"
|
.B "TIOCLINUX, subcode=0"
|
||||||
Dump the screen.
|
Dump the screen.
|
||||||
Disappeared in Linux 1.1.92. (With kernel 1.1.92 or later, read from
|
Disappeared in Linux 1.1.92.
|
||||||
|
(With kernel 1.1.92 or later, read from
|
||||||
.I /dev/vcsN
|
.I /dev/vcsN
|
||||||
or
|
or
|
||||||
.I /dev/vcsaN
|
.I /dev/vcsaN
|
||||||
|
|
|
@ -43,7 +43,8 @@ The
|
||||||
operation requires privilege
|
operation requires privilege
|
||||||
.RB ( CAP_SYS_ADMIN ).
|
.RB ( CAP_SYS_ADMIN ).
|
||||||
.SH RETURN VALUE
|
.SH RETURN VALUE
|
||||||
On success zero is returned. On error, \-1 is returned, and
|
On success zero is returned.
|
||||||
|
On error, \-1 is returned, and
|
||||||
.I errno
|
.I errno
|
||||||
is set to indicate the error.
|
is set to indicate the error.
|
||||||
.SH ERRORS
|
.SH ERRORS
|
||||||
|
@ -77,7 +78,8 @@ The maximum string length for this interface is
|
||||||
.BR FSLABEL_MAX ,
|
.BR FSLABEL_MAX ,
|
||||||
including the terminating null byte (\(aq\\0\(aq).
|
including the terminating null byte (\(aq\\0\(aq).
|
||||||
Filesystems have differing maximum label lengths, which may or
|
Filesystems have differing maximum label lengths, which may or
|
||||||
may not include the terminating null. The string provided to
|
may not include the terminating null.
|
||||||
|
The string provided to
|
||||||
.B FS_IOC_SETFSLABEL
|
.B FS_IOC_SETFSLABEL
|
||||||
must always be null-terminated, and the string returned by
|
must always be null-terminated, and the string returned by
|
||||||
.B FS_IOC_GETFSLABEL
|
.B FS_IOC_GETFSLABEL
|
||||||
|
|
|
@ -71,6 +71,67 @@ Equivalent to
|
||||||
Allow the output buffer to drain, discard pending input, and
|
Allow the output buffer to drain, discard pending input, and
|
||||||
set the current serial port settings.
|
set the current serial port settings.
|
||||||
.PP
|
.PP
|
||||||
|
The following four ioctls, added in Linux 2.6.20,
|
||||||
|
.\" commit 64bb6c5e1ddcd47c951740485026ef08975ee2e6
|
||||||
|
.\" commit 592ee3a5e5e2a981ef2829a0380093006d045661
|
||||||
|
are just like
|
||||||
|
.BR TCGETS ,
|
||||||
|
.BR TCSETS ,
|
||||||
|
.BR TCSETSW ,
|
||||||
|
.BR TCSETSF ,
|
||||||
|
except that they take a
|
||||||
|
.I "struct termios2\ *"
|
||||||
|
instead of a
|
||||||
|
.IR "struct termios\ *" .
|
||||||
|
If the structure member
|
||||||
|
.B c_cflag
|
||||||
|
contains the flag
|
||||||
|
.BR BOTHER ,
|
||||||
|
then the baud rate is stored in the structure members
|
||||||
|
.B c_ispeed
|
||||||
|
and
|
||||||
|
.B c_ospeed
|
||||||
|
as integer values.
|
||||||
|
These ioctls are not supported on all architectures.
|
||||||
|
.RS
|
||||||
|
.TS
|
||||||
|
lb l.
|
||||||
|
TCGETS2 \fBstruct termios2 *\fPargp
|
||||||
|
TCSETS2 \fBconst struct termios2 *\fPargp
|
||||||
|
TCSETSW2 \fBconst struct termios2 *\fPargp
|
||||||
|
TCSETSF2 \fBconst struct termios2 *\fPargp
|
||||||
|
.TE
|
||||||
|
.RE
|
||||||
|
.PP
|
||||||
|
The following four ioctls are just like
|
||||||
|
.BR TCGETS ,
|
||||||
|
.BR TCSETS ,
|
||||||
|
.BR TCSETSW ,
|
||||||
|
.BR TCSETSF ,
|
||||||
|
except that they take a
|
||||||
|
.I "struct termios2\ *"
|
||||||
|
instead of a
|
||||||
|
.IR "struct termios\ *" .
|
||||||
|
If the structure member
|
||||||
|
.B c_cflag
|
||||||
|
contains the flag
|
||||||
|
.B BOTHER
|
||||||
|
then, the baud rate is stored in the structure members
|
||||||
|
.B c_ispeed
|
||||||
|
and
|
||||||
|
.B c_ospeed
|
||||||
|
as integer values.
|
||||||
|
These ioctls are not supported on all architectures.
|
||||||
|
.RS
|
||||||
|
.TS
|
||||||
|
lb l.
|
||||||
|
TCGETS2 \fBstruct termios2 *\fPargp
|
||||||
|
TCSETS2 \fBconst struct termios2 *\fPargp
|
||||||
|
TCSETSW2 \fBconst struct termios2 *\fPargp
|
||||||
|
TCSETSF2 \fBconst struct termios2 *\fPargp
|
||||||
|
.TE
|
||||||
|
.RE
|
||||||
|
.PP
|
||||||
The following four ioctls are just like
|
The following four ioctls are just like
|
||||||
.BR TCGETS ,
|
.BR TCGETS ,
|
||||||
.BR TCSETS ,
|
.BR TCSETS ,
|
||||||
|
@ -701,7 +762,8 @@ Insufficient permission.
|
||||||
Check the condition of DTR on the serial port.
|
Check the condition of DTR on the serial port.
|
||||||
.PP
|
.PP
|
||||||
.EX
|
.EX
|
||||||
#include <termios.h>
|
#include <stdio.h>
|
||||||
|
#include <unistd.h>
|
||||||
#include <fcntl.h>
|
#include <fcntl.h>
|
||||||
#include <sys/ioctl.h>
|
#include <sys/ioctl.h>
|
||||||
|
|
||||||
|
|
|
@ -439,7 +439,8 @@ call.
|
||||||
.B EAGAIN
|
.B EAGAIN
|
||||||
.BR RESOLVE_CACHED
|
.BR RESOLVE_CACHED
|
||||||
was set, and the open operation cannot be performed using only cached
|
was set, and the open operation cannot be performed using only cached
|
||||||
information. The caller should retry without
|
information.
|
||||||
|
The caller should retry without
|
||||||
.B RESOLVE_CACHED
|
.B RESOLVE_CACHED
|
||||||
set in
|
set in
|
||||||
.I how.resolve .
|
.I how.resolve .
|
||||||
|
|
|
@ -141,9 +141,7 @@ are atomic: the data written by
|
||||||
.\" Regarding atomicity, see https://bugzilla.kernel.org/show_bug.cgi?id=10596
|
.\" Regarding atomicity, see https://bugzilla.kernel.org/show_bug.cgi?id=10596
|
||||||
.BR writev ()
|
.BR writev ()
|
||||||
is written as a single block that is not intermingled with output
|
is written as a single block that is not intermingled with output
|
||||||
from writes in other processes (but see
|
from writes in other processes;
|
||||||
.BR pipe (7)
|
|
||||||
for an exception);
|
|
||||||
analogously,
|
analogously,
|
||||||
.BR readv ()
|
.BR readv ()
|
||||||
is guaranteed to read a contiguous block of data from the file,
|
is guaranteed to read a contiguous block of data from the file,
|
||||||
|
|
136
man2/sigaction.2
136
man2/sigaction.2
|
@ -261,6 +261,44 @@ This flag is meaningful only when establishing a signal handler.
|
||||||
.\" .I sa_sigaction
|
.\" .I sa_sigaction
|
||||||
.\" field was added in Linux 2.1.86.)
|
.\" field was added in Linux 2.1.86.)
|
||||||
.\"
|
.\"
|
||||||
|
.TP
|
||||||
|
.B SA_UNSUPPORTED
|
||||||
|
Used to dynamically probe for flag bit support.
|
||||||
|
.IP
|
||||||
|
If an attempt to register a handler succeeds with this flag set in
|
||||||
|
.I act\->sa_flags
|
||||||
|
alongside other flags that are potentially unsupported by the kernel,
|
||||||
|
and an immediately subsequent
|
||||||
|
.BR sigaction ()
|
||||||
|
call specifying the same signal number and with a non-NULL
|
||||||
|
.I oldact
|
||||||
|
argument yields
|
||||||
|
.B SA_UNSUPPORTED
|
||||||
|
.I clear
|
||||||
|
in
|
||||||
|
.IR oldact->sa_flags ,
|
||||||
|
then
|
||||||
|
.I oldact->sa_flags
|
||||||
|
may be used as a bitmask
|
||||||
|
describing which of the potentially unsupported flags are,
|
||||||
|
in fact, supported.
|
||||||
|
See the section "Dynamically probing for flag bit support"
|
||||||
|
below for more details.
|
||||||
|
.TP
|
||||||
|
.BR SA_EXPOSE_TAGBITS " (since Linux 5.11)"
|
||||||
|
Normally, when delivering a signal,
|
||||||
|
an architecture-specific set of tag bits are cleared from the
|
||||||
|
.I si_addr
|
||||||
|
field of
|
||||||
|
.IR siginfo_t .
|
||||||
|
If this flag is set,
|
||||||
|
an architecture-specific subset of the tag bits will be preserved in
|
||||||
|
.IR si_addr .
|
||||||
|
.IP
|
||||||
|
Programs that need to be compatible with Linux versions older than 5.11
|
||||||
|
must use
|
||||||
|
.B SA_UNSUPPORTED
|
||||||
|
to probe for support.
|
||||||
.SS The siginfo_t argument to a SA_SIGINFO handler
|
.SS The siginfo_t argument to a SA_SIGINFO handler
|
||||||
When the
|
When the
|
||||||
.B SA_SIGINFO
|
.B SA_SIGINFO
|
||||||
|
@ -846,6 +884,61 @@ Triggered by a
|
||||||
.BR seccomp (2)
|
.BR seccomp (2)
|
||||||
filter rule.
|
filter rule.
|
||||||
.RE
|
.RE
|
||||||
|
.SS Dynamically probing for flag bit support
|
||||||
|
The
|
||||||
|
.BR sigaction ()
|
||||||
|
call on Linux accepts unknown bits set in
|
||||||
|
.I act\->sa_flags
|
||||||
|
without error.
|
||||||
|
The behavior of the kernel starting with Linux 5.11 is that a second
|
||||||
|
.BR sigaction ()
|
||||||
|
will clear unknown bits from
|
||||||
|
.IR oldact\->sa_flags .
|
||||||
|
However, historically, a second
|
||||||
|
.BR sigaction ()
|
||||||
|
call would typically leave those bits set in
|
||||||
|
.IR oldact\->sa_flags .
|
||||||
|
.PP
|
||||||
|
This means that support for new flags cannot be detected
|
||||||
|
simply by testing for a flag in
|
||||||
|
.IR sa_flags ,
|
||||||
|
and a program must test that
|
||||||
|
.B SA_UNSUPPORTED
|
||||||
|
has been cleared before relying on the contents of
|
||||||
|
.IR sa_flags .
|
||||||
|
.PP
|
||||||
|
Since the behavior of the signal handler cannot be guaranteed
|
||||||
|
unless the check passes,
|
||||||
|
it is wise to either block the affected signal
|
||||||
|
while registering the handler and performing the check in this case,
|
||||||
|
or where this is not possible,
|
||||||
|
for example if the signal is synchronous, to issue the second
|
||||||
|
.BR sigaction ()
|
||||||
|
in the signal handler itself.
|
||||||
|
.PP
|
||||||
|
In kernels that do not support a specific flag,
|
||||||
|
the kernel's behavior is as if the flag was not set,
|
||||||
|
even if the flag was set in
|
||||||
|
.IR act\->sa_flags .
|
||||||
|
.PP
|
||||||
|
The flags
|
||||||
|
.BR SA_NOCLDSTOP ,
|
||||||
|
.BR SA_NOCLDWAIT ,
|
||||||
|
.BR SA_SIGINFO ,
|
||||||
|
.BR SA_ONSTACK ,
|
||||||
|
.BR SA_RESTART ,
|
||||||
|
.BR SA_NODEFER ,
|
||||||
|
.BR SA_RESETHAND ,
|
||||||
|
and, if defined by the architecture,
|
||||||
|
.B SA_RESTORER
|
||||||
|
may not be reliably probed for using this mechanism,
|
||||||
|
because they were introduced before Linux 5.11.
|
||||||
|
However, in general, programs may assume that these flags are supported,
|
||||||
|
since they have all been supported since Linux 2.6,
|
||||||
|
which was released in the year 2003.
|
||||||
|
.PP
|
||||||
|
See EXAMPLES below for a demonstration of the use of
|
||||||
|
.BR SA_UNSUPPORTED .
|
||||||
.SH RETURN VALUE
|
.SH RETURN VALUE
|
||||||
.BR sigaction ()
|
.BR sigaction ()
|
||||||
returns 0 on success; on error, \-1 is returned, and
|
returns 0 on success; on error, \-1 is returned, and
|
||||||
|
@ -1051,6 +1144,49 @@ This bug was fixed in kernel 2.6.14.
|
||||||
.SH EXAMPLES
|
.SH EXAMPLES
|
||||||
See
|
See
|
||||||
.BR mprotect (2).
|
.BR mprotect (2).
|
||||||
|
.SS Probing for flag support
|
||||||
|
The following example program exits with status
|
||||||
|
.B EXIT_SUCCESS
|
||||||
|
if
|
||||||
|
.B SA_EXPOSE_TAGBITS
|
||||||
|
is determined to be supported, and
|
||||||
|
.B EXIT_FAILURE
|
||||||
|
otherwise.
|
||||||
|
.PP
|
||||||
|
.EX
|
||||||
|
#include <signal.h>
|
||||||
|
#include <stdlib.h>
|
||||||
|
#include <stdio.h>
|
||||||
|
#include <unistd.h>
|
||||||
|
|
||||||
|
void
|
||||||
|
handler(int signo, siginfo_t *info, void *context)
|
||||||
|
{
|
||||||
|
struct sigaction oldact;
|
||||||
|
|
||||||
|
if (sigaction(SIGSEGV, NULL, &oldact) == \-1 ||
|
||||||
|
(oldact.sa_flags & SA_UNSUPPORTED) ||
|
||||||
|
!(oldact.sa_flags & SA_EXPOSE_TAGBITS)) {
|
||||||
|
_exit(EXIT_FAILURE);
|
||||||
|
}
|
||||||
|
_exit(EXIT_SUCCESS);
|
||||||
|
}
|
||||||
|
|
||||||
|
int
|
||||||
|
main(void)
|
||||||
|
{
|
||||||
|
struct sigaction act = { 0 };
|
||||||
|
|
||||||
|
act.sa_flags = SA_SIGINFO | SA_UNSUPPORTED | SA_EXPOSE_TAGBITS;
|
||||||
|
act.sa_sigaction = &handler;
|
||||||
|
if (sigaction(SIGSEGV, &act, NULL) == \-1) {
|
||||||
|
perror("sigaction");
|
||||||
|
exit(EXIT_FAILURE);
|
||||||
|
}
|
||||||
|
|
||||||
|
raise(SIGSEGV);
|
||||||
|
}
|
||||||
|
.EE
|
||||||
.SH SEE ALSO
|
.SH SEE ALSO
|
||||||
.BR kill (1),
|
.BR kill (1),
|
||||||
.BR kill (2),
|
.BR kill (2),
|
||||||
|
|
|
@ -412,6 +412,10 @@ T}
|
||||||
.\" Was named sys_kexec_load() from 2.6.7 to 2.6.16
|
.\" Was named sys_kexec_load() from 2.6.7 to 2.6.16
|
||||||
\fBkeyctl\fP(2) 2.6.10
|
\fBkeyctl\fP(2) 2.6.10
|
||||||
\fBkill\fP(2) 1.0
|
\fBkill\fP(2) 1.0
|
||||||
|
\fBlandlock_add_rule\fP(2) 5.13
|
||||||
|
\fBlandlock_create_ruleset\fP(2) 5.13
|
||||||
|
\fBlandlock_restrict_self\fP(2) 5.13
|
||||||
|
\fBlandlock_add_rule\fP(2) 5.13
|
||||||
\fBlchown\fP(2) 1.0 T{
|
\fBlchown\fP(2) 1.0 T{
|
||||||
See \fBchown\fP(2) for
|
See \fBchown\fP(2) for
|
||||||
version details
|
version details
|
||||||
|
@ -562,6 +566,7 @@ T}
|
||||||
\fBpwritev2\fP(2) 4.6
|
\fBpwritev2\fP(2) 4.6
|
||||||
\fBquery_module\fP(2) 2.2 Removed in 2.6
|
\fBquery_module\fP(2) 2.2 Removed in 2.6
|
||||||
\fBquotactl\fP(2) 1.0
|
\fBquotactl\fP(2) 1.0
|
||||||
|
\fBquotactl_path\fP(2) 5.13
|
||||||
\fBread\fP(2) 1.0
|
\fBread\fP(2) 1.0
|
||||||
\fBreadahead\fP(2) 2.4.13
|
\fBreadahead\fP(2) 2.4.13
|
||||||
\fBreaddir\fP(2) 1.0
|
\fBreaddir\fP(2) 1.0
|
||||||
|
|
|
@ -293,7 +293,8 @@ returning the number of bytes actually transferred.
|
||||||
An error return value while performing
|
An error return value while performing
|
||||||
.BR write ()
|
.BR write ()
|
||||||
using direct I/O does not mean the
|
using direct I/O does not mean the
|
||||||
entire write has failed. Partial data may be written
|
entire write has failed.
|
||||||
|
Partial data may be written
|
||||||
and the data at the file offset on which the
|
and the data at the file offset on which the
|
||||||
.BR write ()
|
.BR write ()
|
||||||
was attempted should be considered inconsistent.
|
was attempted should be considered inconsistent.
|
||||||
|
|
|
@ -153,12 +153,15 @@ There are several scenarios when the address of a global symbol is NULL.
|
||||||
For example, a symbol can be placed at zero address by the linker, via
|
For example, a symbol can be placed at zero address by the linker, via
|
||||||
a linker script or with
|
a linker script or with
|
||||||
.I \-\-defsym
|
.I \-\-defsym
|
||||||
command-line option. Undefined weak symbols also have NULL value.
|
command-line option.
|
||||||
|
Undefined weak symbols also have NULL value.
|
||||||
Finally, the symbol value may be the result of
|
Finally, the symbol value may be the result of
|
||||||
a GNU indirect function (IFUNC) resolver function that returns
|
a GNU indirect function (IFUNC) resolver function that returns
|
||||||
NULL as the resolved value. In the latter case,
|
NULL as the resolved value.
|
||||||
|
In the latter case,
|
||||||
.BR dlsym ()
|
.BR dlsym ()
|
||||||
also returns NULL without error. However, in the former two cases, the
|
also returns NULL without error.
|
||||||
|
However, in the former two cases, the
|
||||||
behavior of GNU dynamic linker is inconsistent: relocation processing
|
behavior of GNU dynamic linker is inconsistent: relocation processing
|
||||||
succeeds and the symbol can be observed to have NULL value, but
|
succeeds and the symbol can be observed to have NULL value, but
|
||||||
.BR dlsym ()
|
.BR dlsym ()
|
||||||
|
|
|
@ -130,7 +130,7 @@ A legitimate option character is any visible one byte
|
||||||
.BR ascii (7)
|
.BR ascii (7)
|
||||||
character (for which
|
character (for which
|
||||||
.BR isgraph (3)
|
.BR isgraph (3)
|
||||||
would return nonzero) that is not \(aq\-\(aq or \(aq:\(aq.
|
would return nonzero) that is not \(aq\-\(aq, \(aq:\(aq, or \(aq;\(aq.
|
||||||
If such a
|
If such a
|
||||||
character is followed by a colon, the option requires an argument, so
|
character is followed by a colon, the option requires an argument, so
|
||||||
.BR getopt ()
|
.BR getopt ()
|
||||||
|
@ -166,9 +166,18 @@ If the first character of
|
||||||
.B POSIXLY_CORRECT
|
.B POSIXLY_CORRECT
|
||||||
is set, then option processing stops as soon as a nonoption argument is
|
is set, then option processing stops as soon as a nonoption argument is
|
||||||
encountered.
|
encountered.
|
||||||
|
If \(aq+\(aq is not the first character of
|
||||||
|
.IR optstring ,
|
||||||
|
it is treated as a normal option.
|
||||||
|
If
|
||||||
|
.B POSIXLY_CORRECT
|
||||||
|
behaviour is required in this case
|
||||||
|
.I optstring
|
||||||
|
will contain two \(aq+\(aq symbols.
|
||||||
If the first character of \fIoptstring\fP is \(aq\-\(aq, then
|
If the first character of \fIoptstring\fP is \(aq\-\(aq, then
|
||||||
each nonoption \fIargv\fP-element is handled as if it were the argument of
|
each nonoption \fIargv\fP-element is handled as if it were the argument of
|
||||||
an option with character code 1. (This is used by programs that were
|
an option with character code 1.
|
||||||
|
(This is used by programs that were
|
||||||
written to expect options and other \fIargv\fP-elements in any order
|
written to expect options and other \fIargv\fP-elements in any order
|
||||||
and that care about the ordering of the two.)
|
and that care about the ordering of the two.)
|
||||||
The special argument "\-\-" forces an end of option-scanning regardless
|
The special argument "\-\-" forces an end of option-scanning regardless
|
||||||
|
|
|
@ -111,7 +111,7 @@ conversion specification.)
|
||||||
.BR T_FMT_AMPM \ (LC_TIME)
|
.BR T_FMT_AMPM \ (LC_TIME)
|
||||||
Return a string that can be used as a format string for
|
Return a string that can be used as a format string for
|
||||||
.BR strftime (3)
|
.BR strftime (3)
|
||||||
to represent a time in a.m. or p.m. notation a locale-specific way
|
to represent a time in a.m. or p.m. notation in a locale-specific way
|
||||||
.RB ( %r
|
.RB ( %r
|
||||||
conversion specification).
|
conversion specification).
|
||||||
.TP
|
.TP
|
||||||
|
@ -200,7 +200,8 @@ for alternative representation of a time in a locale-specific way
|
||||||
conversion specification).
|
conversion specification).
|
||||||
.TP
|
.TP
|
||||||
.BR DAY_ "{1\(en7} (LC_TIME)"
|
.BR DAY_ "{1\(en7} (LC_TIME)"
|
||||||
Return name of the \fIn\fP-th day of the week. [Warning: this follows
|
Return name of the \fIn\fP-th day of the week.
|
||||||
|
[Warning: this follows
|
||||||
the US convention DAY_1 = Sunday, not the international convention
|
the US convention DAY_1 = Sunday, not the international convention
|
||||||
(ISO 8601) that Monday is the first day of the week.]
|
(ISO 8601) that Monday is the first day of the week.]
|
||||||
(Used in
|
(Used in
|
||||||
|
|
|
@ -66,8 +66,8 @@ All regular expression searching must be done via a compiled pattern
|
||||||
buffer, thus
|
buffer, thus
|
||||||
.BR regexec ()
|
.BR regexec ()
|
||||||
must always be supplied with the address of a
|
must always be supplied with the address of a
|
||||||
.BR regcomp ()
|
.BR regcomp ()-initialized
|
||||||
initialized pattern buffer.
|
pattern buffer.
|
||||||
.PP
|
.PP
|
||||||
.I cflags
|
.I cflags
|
||||||
is the
|
is the
|
||||||
|
|
|
@ -331,7 +331,8 @@ Ignore modem control lines.
|
||||||
.TP
|
.TP
|
||||||
.B LOBLK
|
.B LOBLK
|
||||||
(not in POSIX) Block output from a noncurrent shell layer.
|
(not in POSIX) Block output from a noncurrent shell layer.
|
||||||
For use by \fBshl\fP (shell layers). (Not implemented on Linux.)
|
For use by \fBshl\fP (shell layers).
|
||||||
|
(Not implemented on Linux.)
|
||||||
.TP
|
.TP
|
||||||
.B CIBAUD
|
.B CIBAUD
|
||||||
(not in POSIX) Mask for input speeds.
|
(not in POSIX) Mask for input speeds.
|
||||||
|
@ -945,24 +946,76 @@ to by \fItermios_p\fP to \fIspeed\fP, which must be one of these constants:
|
||||||
B57600
|
B57600
|
||||||
B115200
|
B115200
|
||||||
B230400
|
B230400
|
||||||
|
B460800
|
||||||
|
B500000
|
||||||
|
B576000
|
||||||
|
B921600
|
||||||
|
B1000000
|
||||||
|
B1152000
|
||||||
|
B1500000
|
||||||
|
B2000000
|
||||||
.ft P
|
.ft P
|
||||||
.fi
|
.fi
|
||||||
.PP
|
.PP
|
||||||
The zero baud rate, \fBB0\fP,
|
These constants are additionally supported on the SPARC architecture:
|
||||||
|
.PP
|
||||||
|
.nf
|
||||||
|
.ft B
|
||||||
|
B76800
|
||||||
|
B153600
|
||||||
|
B307200
|
||||||
|
B614400
|
||||||
|
.ft P
|
||||||
|
.fi
|
||||||
|
.PP
|
||||||
|
These constants are additionally supported on non-SPARC architectures:
|
||||||
|
.PP
|
||||||
|
.nf
|
||||||
|
.ft B
|
||||||
|
B2500000
|
||||||
|
B3000000
|
||||||
|
B3500000
|
||||||
|
B4000000
|
||||||
|
.ft P
|
||||||
|
.fi
|
||||||
|
.PP
|
||||||
|
Due to differences between architectures, portable applications should check
|
||||||
|
if a particular
|
||||||
|
.BI B nnn
|
||||||
|
constant is defined prior to using it.
|
||||||
|
.PP
|
||||||
|
The zero baud rate,
|
||||||
|
.BR B0 ,
|
||||||
is used to terminate the connection.
|
is used to terminate the connection.
|
||||||
If B0 is specified, the modem control lines shall no longer be asserted.
|
If B0 is specified, the modem control lines shall no longer be asserted.
|
||||||
Normally, this will disconnect the line.
|
Normally, this will disconnect the line.
|
||||||
\fBCBAUDEX\fP is a mask
|
.B CBAUDEX
|
||||||
|
is a mask
|
||||||
for the speeds beyond those defined in POSIX.1 (57600 and above).
|
for the speeds beyond those defined in POSIX.1 (57600 and above).
|
||||||
Thus, \fBB57600\fP & \fBCBAUDEX\fP is nonzero.
|
Thus,
|
||||||
|
.BR B57600 " & " CBAUDEX
|
||||||
|
is nonzero.
|
||||||
|
.PP
|
||||||
|
Setting the baud rate to a value other than those defined by
|
||||||
|
.BI B nnn
|
||||||
|
constants is possible via the
|
||||||
|
.B TCSETS2
|
||||||
|
ioctl; see
|
||||||
|
.BR ioctl_tty (2).
|
||||||
.PP
|
.PP
|
||||||
.BR cfgetispeed ()
|
.BR cfgetispeed ()
|
||||||
returns the input baud rate stored in the \fItermios\fP structure.
|
returns the input baud rate stored in the
|
||||||
|
.I termios
|
||||||
|
structure.
|
||||||
.PP
|
.PP
|
||||||
.BR cfsetispeed ()
|
.BR cfsetispeed ()
|
||||||
sets the input baud rate stored in the \fItermios\fP structure to
|
sets the input baud rate stored in the
|
||||||
|
.I termios
|
||||||
|
structure to
|
||||||
.IR speed ,
|
.IR speed ,
|
||||||
which must be specified as one of the \fBBnnn\fP constants listed above for
|
which must be specified as one of the
|
||||||
|
.BI B nnn
|
||||||
|
constants listed above for
|
||||||
.BR cfsetospeed ().
|
.BR cfsetospeed ().
|
||||||
If the input baud rate is set to zero, the input baud rate will be
|
If the input baud rate is set to zero, the input baud rate will be
|
||||||
equal to the output baud rate.
|
equal to the output baud rate.
|
||||||
|
@ -1056,8 +1109,14 @@ and
|
||||||
are nonstandard, but available on the BSDs.
|
are nonstandard, but available on the BSDs.
|
||||||
.SH NOTES
|
.SH NOTES
|
||||||
UNIX\ V7 and several later systems have a list of baud rates
|
UNIX\ V7 and several later systems have a list of baud rates
|
||||||
where after the fourteen values B0, ..., B9600 one finds the
|
where after the values
|
||||||
two constants EXTA, EXTB ("External A" and "External B").
|
.BR B0
|
||||||
|
through
|
||||||
|
.B B9600
|
||||||
|
one finds the two constants
|
||||||
|
.BR EXTA ,
|
||||||
|
.B EXTB
|
||||||
|
("External A" and "External B").
|
||||||
Many systems extend the list with much higher baud rates.
|
Many systems extend the list with much higher baud rates.
|
||||||
.PP
|
.PP
|
||||||
The effect of a nonzero \fIduration\fP with
|
The effect of a nonzero \fIduration\fP with
|
||||||
|
|
|
@ -24,8 +24,8 @@ xencrypt, xdecrypt, passwd2des \- RFS password encryption
|
||||||
.fi
|
.fi
|
||||||
.SH DESCRIPTION
|
.SH DESCRIPTION
|
||||||
.BR WARNING :
|
.BR WARNING :
|
||||||
Do not use these functions in new code. They do not achieve
|
Do not use these functions in new code.
|
||||||
any type of acceptable cryptographic security guarantees.
|
They do not achieve any type of acceptable cryptographic security guarantees.
|
||||||
.PP
|
.PP
|
||||||
The function
|
The function
|
||||||
.BR passwd2des ()
|
.BR passwd2des ()
|
||||||
|
|
|
@ -38,7 +38,8 @@ You can explicitly deny access to a host by preceding the
|
||||||
.I hostname
|
.I hostname
|
||||||
by a minus (\-) sign.
|
by a minus (\-) sign.
|
||||||
Users from that host must always supply additional credentials,
|
Users from that host must always supply additional credentials,
|
||||||
including possibly a password. For security reasons you should always
|
including possibly a password.
|
||||||
|
For security reasons you should always
|
||||||
use the FQDN of the hostname and not the short hostname.
|
use the FQDN of the hostname and not the short hostname.
|
||||||
.PP
|
.PP
|
||||||
The
|
The
|
||||||
|
|
|
@ -102,9 +102,10 @@ Shadow user passwords, used by
|
||||||
.BR getspnam (3)
|
.BR getspnam (3)
|
||||||
and related functions.
|
and related functions.
|
||||||
.PP
|
.PP
|
||||||
The GNU C Library ignores databases with unknown names. Some
|
The GNU C Library ignores databases with unknown names.
|
||||||
applications use this to implement special handling for their own
|
Some applications use this to implement special handling for their own
|
||||||
databases. For example,
|
databases.
|
||||||
|
For example,
|
||||||
.BR sudo (8)
|
.BR sudo (8)
|
||||||
consults the
|
consults the
|
||||||
.B sudoers
|
.B sudoers
|
||||||
|
|
|
@ -92,8 +92,8 @@ was eventually made official with the release of Linux 4.5.
|
||||||
Differences between the two versions are described in the text below.
|
Differences between the two versions are described in the text below.
|
||||||
The file
|
The file
|
||||||
.IR cgroup.sane_behavior ,
|
.IR cgroup.sane_behavior ,
|
||||||
present in cgroups v1, is a relic of this mount option. The file
|
present in cgroups v1, is a relic of this mount option.
|
||||||
always reports "0" and is only retained for backward compatibility.
|
The file always reports "0" and is only retained for backward compatibility.
|
||||||
.PP
|
.PP
|
||||||
Although cgroups v2 is intended as a replacement for cgroups v1,
|
Although cgroups v2 is intended as a replacement for cgroups v1,
|
||||||
the older system continues to exist
|
the older system continues to exist
|
||||||
|
|
|
@ -525,7 +525,8 @@ If there is a single such prototype that needs to be continued,
|
||||||
then align the continuation line so that when the page is
|
then align the continuation line so that when the page is
|
||||||
rendered on a fixed-width font device (e.g., on an xterm) the
|
rendered on a fixed-width font device (e.g., on an xterm) the
|
||||||
continuation line starts just below the start of the argument
|
continuation line starts just below the start of the argument
|
||||||
list in the line above. (Exception: the indentation may be
|
list in the line above.
|
||||||
|
(Exception: the indentation may be
|
||||||
adjusted if necessary to prevent a very long continuation line
|
adjusted if necessary to prevent a very long continuation line
|
||||||
or a further continuation line where the function prototype is
|
or a further continuation line where the function prototype is
|
||||||
very long.)
|
very long.)
|
||||||
|
@ -541,7 +542,8 @@ As an example:
|
||||||
But, where multiple functions in the SYNOPSIS require
|
But, where multiple functions in the SYNOPSIS require
|
||||||
continuation lines, and the function names have different
|
continuation lines, and the function names have different
|
||||||
lengths, then align all continuation lines to start in the
|
lengths, then align all continuation lines to start in the
|
||||||
same column. This provides a nicer rendering in PDF output
|
same column.
|
||||||
|
This provides a nicer rendering in PDF output
|
||||||
(because the SYNOPSIS uses a variable width font where
|
(because the SYNOPSIS uses a variable width font where
|
||||||
spaces render narrower than most characters).
|
spaces render narrower than most characters).
|
||||||
As an example:
|
As an example:
|
||||||
|
@ -638,7 +640,7 @@ makes it easier to write tools that parse man page source files.)
|
||||||
.SS Use semantic newlines
|
.SS Use semantic newlines
|
||||||
In the source of a manual page,
|
In the source of a manual page,
|
||||||
new sentences should be started on new lines,
|
new sentences should be started on new lines,
|
||||||
and long sentences should split into lines at clause breaks
|
and long sentences should be split into lines at clause breaks
|
||||||
(commas, semicolons, colons, and so on).
|
(commas, semicolons, colons, and so on).
|
||||||
This convention, sometimes known as "semantic newlines",
|
This convention, sometimes known as "semantic newlines",
|
||||||
makes it easier to see the effect of patches,
|
makes it easier to see the effect of patches,
|
||||||
|
|
|
@ -71,7 +71,8 @@ Time CLONE_NEWTIME \fBtime_namespaces\fP(7) T{
|
||||||
Boot and monotonic
|
Boot and monotonic
|
||||||
clocks
|
clocks
|
||||||
T}
|
T}
|
||||||
User CLONE_NEWUSER \fBuser_namespaces\fP(7) T{User and group IDs
|
User CLONE_NEWUSER \fBuser_namespaces\fP(7) T{
|
||||||
|
User and group IDs
|
||||||
T}
|
T}
|
||||||
UTS CLONE_NEWUTS \fButs_namespaces\fP(7) T{
|
UTS CLONE_NEWUTS \fButs_namespaces\fP(7) T{
|
||||||
Hostname and NIS
|
Hostname and NIS
|
||||||
|
|
|
@ -189,7 +189,8 @@ message signals an error and the payload contains an
|
||||||
.I nlmsgerr
|
.I nlmsgerr
|
||||||
structure,
|
structure,
|
||||||
.B NLMSG_DONE
|
.B NLMSG_DONE
|
||||||
message terminates a multipart message. Error messages get the
|
message terminates a multipart message.
|
||||||
|
Error messages get the
|
||||||
original request appened, unless the user requests to cap the
|
original request appened, unless the user requests to cap the
|
||||||
error message, and get extra error data if requested.
|
error message, and get extra error data if requested.
|
||||||
.PP
|
.PP
|
||||||
|
|
|
@ -177,10 +177,11 @@ with the
|
||||||
flag set (though note that this also restricts bind mount traversal).
|
flag set (though note that this also restricts bind mount traversal).
|
||||||
.SS Trailing slashes
|
.SS Trailing slashes
|
||||||
If a pathname ends in a \(aq/\(aq, that forces resolution of the preceding
|
If a pathname ends in a \(aq/\(aq, that forces resolution of the preceding
|
||||||
component as in Step 2: it has to exist and resolve to a directory.
|
component as in Step 2:
|
||||||
|
the component preceding the slash either exists and resolves to a directory
|
||||||
|
of it names a directory that is to be created immediately after the
|
||||||
|
pathname is resolved.
|
||||||
Otherwise, a trailing \(aq/\(aq is ignored.
|
Otherwise, a trailing \(aq/\(aq is ignored.
|
||||||
(Or, equivalently, a pathname with a trailing \(aq/\(aq is equivalent to
|
|
||||||
the pathname obtained by appending \(aq.\(aq to it.)
|
|
||||||
.SS Final symlink
|
.SS Final symlink
|
||||||
If the last component of a pathname is a symbolic link, then it
|
If the last component of a pathname is a symbolic link, then it
|
||||||
depends on the system call whether the file referred to will be
|
depends on the system call whether the file referred to will be
|
||||||
|
|
|
@ -244,9 +244,7 @@ and
|
||||||
limits; see BUGS.
|
limits; see BUGS.
|
||||||
.\"
|
.\"
|
||||||
.SS PIPE_BUF
|
.SS PIPE_BUF
|
||||||
POSIX.1 says that
|
POSIX.1 says that writes of less than
|
||||||
.BR write (2)s
|
|
||||||
of less than
|
|
||||||
.B PIPE_BUF
|
.B PIPE_BUF
|
||||||
bytes must be atomic: the output data is written to the pipe as a
|
bytes must be atomic: the output data is written to the pipe as a
|
||||||
contiguous sequence.
|
contiguous sequence.
|
||||||
|
|
|
@ -1247,7 +1247,8 @@ Alternatively,
|
||||||
or
|
or
|
||||||
.IR <wordexp.h> .
|
.IR <wordexp.h> .
|
||||||
.PP
|
.PP
|
||||||
Used for a count of bytes. It is the result of the
|
Used for a count of bytes.
|
||||||
|
It is the result of the
|
||||||
.I sizeof
|
.I sizeof
|
||||||
operator.
|
operator.
|
||||||
According to the C language standard,
|
According to the C language standard,
|
||||||
|
|
|
@ -819,7 +819,7 @@ reference to it is closed.
|
||||||
To pass file descriptors or credentials over a
|
To pass file descriptors or credentials over a
|
||||||
.BR SOCK_STREAM
|
.BR SOCK_STREAM
|
||||||
socket, you must
|
socket, you must
|
||||||
to send or receive at least one byte of nonancillary data in the same
|
send or receive at least one byte of nonancillary data in the same
|
||||||
.BR sendmsg (2)
|
.BR sendmsg (2)
|
||||||
or
|
or
|
||||||
.BR recvmsg (2)
|
.BR recvmsg (2)
|
||||||
|
|
Loading…
Reference in New Issue