.fp 5 CW

.de Af

.ds ;G \\*(;G\\f\\$1\\$3\\f\\$2

.if !\\$4 .Af \\$2 \\$1 "\\$4" "\\$5" "\\$6" "\\$7" "\\$8" "\\$9"

..

.de aF

.ie \\$3 .ft \\$1

.el \{\

.ds ;G \&

.nr ;G \\n(.f

.Af "\\$1" "\\$2" "\\$3" "\\$4" "\\$5" "\\$6" "\\$7" "\\$8" "\\$9"

\\*(;G

.ft \\n(;G \}

..

.de L

.aF 5 \\n(.f "\\$1" "\\$2" "\\$3" "\\$4" "\\$5" "\\$6" "\\$7"

..

.de LR

.aF 5 1 "\\$1" "\\$2" "\\$3" "\\$4" "\\$5" "\\$6" "\\$7"

..

.de RL

.aF 1 5 "\\$1" "\\$2" "\\$3" "\\$4" "\\$5" "\\$6" "\\$7"

..

.de EX \" start example

.ta 1i 2i 3i 4i 5i 6i

.PP

.RS

.PD 0

.ft 5

.nf

..

.de EE \" end example

.fi

.ft

.PD

.RE

.PP

..

.TH MODECANON 3

.SH NAME

modecanon \- canonical file mode representation

.SH SYNOPSIS

#include <modex.h>

int modei(int \fIexternal\fP);

int modex(int \fIinternal\fP);

.EE

.SH DESCRIPTION

POSIX threw out the file type bit macros and replaced them with

function-like macros that test file type.

This is bad in many ways, the worst of which is that it provides

no way for a user program to synthesize file types in the mode bits.

.IR pax (1),

.IR tar (1)

and

.IR cpio (1)

are examples of user programs that must convert between the internal mode

representation and a private external representation.

These routines provide a canonical external representation

with macros to access and synthesize the bits in the external

representation.

.PP

.L modei

takes an external mode representation

.I external

and returns the equivalent internal representation.

.PP

.L modex

takes an internal mode representation

.I internal

and returns the equivalent external representation.

.PP

The traditional bit access macro (\f5S_\fP prefix changes to \f5X_\fP) are:

.L X_IFMT ,

.L X_IFSOCK ,

.L X_IFLNK ,

.L X_IFCTG ,

.L X_IFREG ,

.L X_IFBLK ,

.L X_IFDIR ,

.L X_IFCHR ,

.L X_IFIFO ,

.L X_IPERM ,

.L X_ISUID ,

.L X_ISGID ,

.L X_ISVTX ,

.L X_IRUSR ,

.L X_IWUSR ,

.L X_IXUSR ,

.L X_IRGRP ,

.L X_IWGRP ,

.L X_IXGRP ,

.L X_IROTH ,

.L X_IWOTH ,

.L X_IXOTH ,

.L X_IRWXU ,

.L X_IRWXG

and

.L X_IRWXO .

.LI X_ITYPE( mode )

returns the type bits for

.IR mode .

.SH "SEE ALSO"

pax(1), stat(2)