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-rw-r--r--man2/process_vm_readv.236
1 files changed, 18 insertions, 18 deletions
diff --git a/man2/process_vm_readv.2 b/man2/process_vm_readv.2
index 86da35c..23c9111 100644
--- a/man2/process_vm_readv.2
+++ b/man2/process_vm_readv.2
@@ -6,7 +6,7 @@
.\"
.\" Commit fcf634098c00dd9cd247447368495f0b79be12d1
.\"
-.TH process_vm_readv 2 2023-05-03 "Linux man-pages 6.05.01"
+.TH process_vm_readv 2 2023-10-31 "Linux man-pages 6.7"
.SH NAME
process_vm_readv, process_vm_writev \-
transfer data between process address spaces
@@ -16,7 +16,7 @@ Standard C library
.SH SYNOPSIS
.nf
.B #include <sys/uio.h>
-.PP
+.P
.BI "ssize_t process_vm_readv(pid_t " pid ,
.BI " const struct iovec *" local_iov ,
.BI " unsigned long " liovcnt ,
@@ -30,12 +30,12 @@ Standard C library
.BI " unsigned long " riovcnt ,
.BI " unsigned long " flags ");"
.fi
-.PP
+.P
.RS -4
Feature Test Macro Requirements for glibc (see
.BR feature_test_macros (7)):
.RE
-.PP
+.P
.BR process_vm_readv (),
.BR process_vm_writev ():
.nf
@@ -48,7 +48,7 @@ of the calling process ("the local process") and the process identified by
("the remote process").
The data moves directly between the address spaces of the two processes,
without passing through kernel space.
-.PP
+.P
The
.BR process_vm_readv ()
system call transfers data from the remote process to the local process.
@@ -73,7 +73,7 @@ and
.I liovcnt
specifies the number of elements in
.IR local_iov .
-.PP
+.P
The
.BR process_vm_writev ()
system call is the converse of
@@ -87,7 +87,7 @@ and
.I remote_iov
have the same meaning as for
.BR process_vm_readv ().
-.PP
+.P
The
.I local_iov
and
@@ -96,7 +96,7 @@ arguments point to an array of
.I iovec
structures, described in
.BR iovec (3type).
-.PP
+.P
Buffers are processed in array order.
This means that
.BR process_vm_readv ()
@@ -110,7 +110,7 @@ Likewise,
is completely read before proceeding to
.IR remote_iov[1] ,
and so on.
-.PP
+.P
Similarly,
.BR process_vm_writev ()
writes out the entire contents of
@@ -121,7 +121,7 @@ and it completely fills
.I remote_iov[0]
before proceeding to
.IR remote_iov[1] .
-.PP
+.P
The lengths of
.I remote_iov[i].iov_len
and
@@ -129,11 +129,11 @@ and
do not have to be the same.
Thus, it is possible to split a single local buffer
into multiple remote buffers, or vice versa.
-.PP
+.P
The
.I flags
argument is currently unused and must be set to 0.
-.PP
+.P
The values specified in the
.I liovcnt
and
@@ -146,7 +146,7 @@ or accessible via the call
.IR sysconf(_SC_IOV_MAX) ).
.\" In time, glibc might provide a wrapper that works around this limit,
.\" as is done for readv()/writev()
-.PP
+.P
The count arguments and
.I local_iov
are checked before doing any transfers.
@@ -156,7 +156,7 @@ is invalid,
or the addresses refer to regions that are inaccessible to the local process,
none of the vectors will be processed
and an error will be returned immediately.
-.PP
+.P
Note, however, that these system calls do not check the memory regions
in the remote process until just before doing the read/write.
Consequently, a partial read/write (see RETURN VALUE)
@@ -176,7 +176,7 @@ elements and have them merge back into a single write
entry.
The first read entry goes up to the page boundary,
while the second starts on the next page boundary.)
-.PP
+.P
Permission to read from or write to another process
is governed by a ptrace access mode
.B PTRACE_MODE_ATTACH_REALCREDS
@@ -198,7 +198,7 @@ These system calls won't perform a partial transfer that splits a single
element.)
The caller should check the return value to determine whether
a partial read/write occurred.
-.PP
+.P
On error, \-1 is returned and
.I errno
is set to indicate the error.
@@ -260,7 +260,7 @@ The data transfers performed by
and
.BR process_vm_writev ()
are not guaranteed to be atomic in any way.
-.PP
+.P
These system calls were designed to permit fast message passing
by allowing messages to be exchanged with a single copy operation
(rather than the double copy that would be required
@@ -276,7 +276,7 @@ and writes the first 10 bytes into
.I buf1
and the second 10 bytes into
.IR buf2 .
-.PP
+.P
.\" SRC BEGIN (process_vm_readv.c)
.EX
#define _GNU_SOURCE