$buffer-fmod(5)

NAME

$buffer-fmod - Buffer file modes (or attributes)
$global-fmod - Global file modes (or attributes)

SYNOPSIS

$buffer-fmod FileMode
$global-fmod FileMode

DESCRIPTION

$buffer-fmod is bit based variable setting the buffers file system modes or attributes. If the buffer was loaded from an existing file then the value of $buffer-fmod is taken directly from the file. But if the buffer was created then the buffer inherits the default file modes, $global-fmod, which is determined from the users umask on UNIX or a default on others.

Note that the retrieved value of $buffer-fmod can be different to the set value, see the NOTES section below.

The definition of the file mode bits are platform specific and are considered independently, as follows:

UNIX

The file modes of Unix are the standard read, write and execute permissions for user, group and global. See chmod(1) for a full description of their use and effect.

The variable is displayed in octal.

Microsoft Windows and DOS

On Microsoft platforms each file attribute (see attrib(1)) is assigned a bit, on windows 95 and NT the new file attributes such as compressed are also represented. The bits are assigned as follows

Bit     Attrib Flag     Attribute 
0x001       R           Read Only 
0x002       H           Hidden 
0x004       S           System 
0x010                   Directory 
0x020       A           Archive 
0x080                   Normal 
0x100                   Temporary 
0x800                   Compressed 

EXAMPLE

The following example changes the $buffer-fmod so that the file will be executable (UNIX only), useful when writing a shell script.

set-variable $buffer-fmod 0775 

NOTES

When retrieved, the buffer's file flags are also merged into the value of $buffer-fmod. These flags are not platform specific and used to store the current properties of the buffer's file. They cannot be set and are defined as follows:

0x10000


When set the buffer is a directory listing, created by the find-file(2) command when the file name given is a directory. Earlier versions of MicroEmacs had a dir buffer mode, this mode has been removed as this property cannot be simply toggled like other modes. Checking the value of this bit should be used instead.

0x20000


When set the file was found to contain binary data that cannot be safely represented in a buffer, as a result saving the buffer will result in data loss and corruption. Note that this is different to binary(2m) or rbin(2m) buffer modes which can safely represent any binary data, i.e. a file loaded with binary mode enabled will never have this bit set.

0x40000


When set the file was found to contain inconsistent line terminations, i.e. typically some lines terminated with '\n' and others with '\r\n'. Saving the file will unify/correct the line terminations, but this could be a corruption.

SEE ALSO

find-file(2), cr(2m), lf(2m), binary(2m), ctrlz(2m), auto(2m).

Ref: $buffer-fmod(5) File: m5var070.5 Date: 2026/02/17

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