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.TH "SKB_COPY_EXPAND" "9" "07 August 2003" "" ""

.SH NAME
skb_copy_expand \- copy and expand sk_buff
.SH SYNOPSIS
.sp
\fB
.sp
struct sk_buff * skb_copy_expand  (const struct sk_buff * \fIskb\fB, int \fInewheadroom\fB, int \fInewtailroom\fB, int \fIgfp_mask\fB);
\fR
.SH "ARGUMENTS"
.TP
\fB\fIskb\fB\fR
buffer to copy
.TP
\fB\fInewheadroom\fB\fR
new free bytes at head
.TP
\fB\fInewtailroom\fB\fR
new free bytes at tail
.TP
\fB\fIgfp_mask\fB\fR
allocation priority
.SH "DESCRIPTION"
.PP
Make a copy of both an &sk_buff and its data and while doing so
allocate additional space.
.PP
This is used when the caller wishes to modify the data and needs a
private copy of the data to alter as well as more space for new fields.
Returns NULL on failure or the pointer to the buffer
on success. The returned buffer has a reference count of 1.
.PP
You must pass GFP_ATOMIC as the allocation priority if this function
is called from an interrupt.
.SH "BUG ALERT"
.PP
ip_summed is not copied. Why does this work? Is it used
only by netfilter in the cases when checksum is recalculated? --ANK
.SH "ABOUT THIS DOCUMENT"
.PP
This documentation was generated with kernel version 2.6.0.