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You can write the contents of a buffer, or part of a buffer, directly
to a file on disk using the append-to-file
and
write-region
functions. Don’t use these functions to write to
files that are being visited; that could cause confusion in the
mechanisms for visiting.
This function appends the contents of the region delimited by
start and end in the current buffer to the end of file
filename. If that file does not exist, it is created. If that
file exists it is overwritten. This function returns nil
.
An error is signaled if filename specifies a nonwritable file, or a nonexistent file in a directory where files cannot be created.
This function writes the region delimited by start and end in the current buffer into the file specified by filename.
If start is a string, then write-region
writes or appends
that string, rather than text from the buffer.
If append is non-nil
, then the specified text is appended
to the existing file contents (if any).
If visit is t
, then SXEmacs establishes an association
between the buffer and the file: the buffer is then visiting that file.
It also sets the last file modification time for the current buffer to
filename’s modtime, and marks the buffer as not modified. This
feature is used by save-buffer
, but you probably should not use
it yourself.
If visit is a string, it specifies the file name to visit. This
way, you can write the data to one file (filename) while recording
the buffer as visiting another file (visit). The argument
visit is used in the echo area message and also for file locking;
visit is stored in buffer-file-name
. This feature is used
to implement file-precious-flag
; don’t use it yourself unless you
really know what you’re doing.
The function write-region
converts the data which it writes to
the appropriate file formats specified by buffer-file-format
.
See Format Conversion. It also calls the functions in the list
write-region-annotate-functions
; see Saving Properties.
Normally, write-region
displays a message ‘Wrote file
filename’ in the echo area. If visit is neither t
nor nil
nor a string, then this message is inhibited. This
feature is useful for programs that use files for internal purposes,
files that the user does not need to know about.
Next: File Locks, Previous: Reading from Files, Up: Files [Contents][Index]