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6 tar File Creation

 (require file/tar) package: base
The file/tar library provides utilities to create archive files in USTAR format, like the archive that the Unix utility pax generates. Long paths are supported using either the POSIX.1-2001/pax or GNU format for long paths. The resulting archives contain only directories, files, and symbolic links, and owner information is not preserved; the owner that is stored in the archive is always “root.”
Symbolic links (on Unix and Mac OS) are not followed by default.

procedure

(tar tar-file 
  path ... 
  [#:follow-links? follow-links? 
  #:exists-ok? exists-ok? 
  #:format format 
  #:path-prefix path-prefix 
  #:path-filter path-filter 
  #:get-timestamp get-timestamp]) 
 → exact-nonnegative-integer?
  tar-file : path-string?
  path : path-string?
  follow-links? : any/c = #f
  exists-ok? : any/c = #f
  format : (or/c 'pax 'gnu 'ustar) = 'pax
  path-prefix : (or/c #f path-string?) = #f
  path-filter : (or/c #f (path? . -> . any/c)) = #f
  get-timestamp : (path? . -> . exact-integer?)
   = 
(if timestamp
    (lambda (p) timestamp)
    file-or-directory-modify-seconds)
Creates tar-file, which holds the complete content of all paths. The given paths are all expected to be relative paths for existing directories and files (i.e., relative to the current directory). If a nested path is provided as a path, its ancestor directories are also added to the resulting tar file, up to the current directory (using pathlist-closure). If follow-links? is false, then symbolic links are included in the resulting tar file as links.

If exists-ok? is #f, then an exception is raised if tar-file exists already. If exists-ok? is true, then tar-file is truncated or replaced if it exists already.

The format argument determines the handling of long paths and long symbolic-link targets. If format is 'pax, then POSIX.1-2001/pax extensions are used. If format is 'gnu, then GNU extensions are used. If format is 'ustar, then tar raises an error for too-long paths or symbolic-link targets.

If path-prefix is not #f, then it is prefixed to each path in the archive.

The get-timestamp function is used to obtain the modification date to record in the archive for each file or directory.

Changed in version 6.0.0.3 of package base: Added the #:get-timestamp argument. Changed in version 6.1.1.1: Added the #:exists-ok? argument. Changed in version 6.3.0.3: Added the #:follow-links? argument. Changed in version 6.3.0.11: Added the #:path-filter argument. Changed in version 6.7.0.4: Added the #:format argument and effectively changed its default from 'ustar to 'pax.

procedure

(tar->output paths 
  [out 
  #:follow-links? follow-links? 
  #:format format 
  #:path-prefix path-prefix 
  #:path-filter path-filter 
  #:get-timestamp get-timestamp]) 
 → exact-nonnegative-integer?
  paths : (listof path?)
  out : output-port? = (current-output-port)
  follow-links? : any/c = #f
  format : (or/c 'pax 'gnu 'ustar) = 'pax
  path-prefix : (or/c #f path-string?) = #f
  path-filter : (or/c #f (path? . -> . any/c)) = #f
  get-timestamp : (path? . -> . exact-integer?)
   = 
(if timestamp
    (lambda (p) timestamp)
    file-or-directory-modify-seconds)
Like tar, but packages each of the given paths in a tar format archive that is written directly to the out. The specified paths are included as-is (except for adding path-prefix, if any); if a directory is specified, its content is not automatically added, and nested directories are added without parent directories.

Changed in version 6.0.0.3 of package base: Added the #:get-timestamp argument. Changed in version 6.3.0.3: Added the #:follow-links? argument. Changed in version 6.3.0.11: Added the #:path-filter argument. Changed in version 6.7.0.4: Added the #:format argument and effectively changed its default from 'ustar to 'pax.

procedure

(tar-gzip tar-file    
  paths ...    
  [#:follow-links? follow-links?    
  #:exists-ok? exists-ok?    
  #:format format    
  #:path-prefix path-prefix    
  #:get-timestamp get-timestamp]) → void?
  tar-file : path-string?
  paths : path-string?
  follow-links? : any/c = #f
  exists-ok? : any/c = #f
  format : (or/c 'pax 'gnu 'ustar) = 'pax
  path-prefix : (or/c #f path-string?) = #f
  get-timestamp : (path? . -> . exact-integer?)
   = 
(if timestamp
    (lambda (p) timestamp)
    file-or-directory-modify-seconds)
Like tar, but compresses the resulting file with gzip.

Changed in version 6.0.0.3 of package base: Added the #:get-timestamp argument. Changed in version 6.1.1.1: Added the #:exists-ok? argument. Changed in version 6.3.0.3: Added the #:follow-links? argument. Changed in version 6.7.0.4: Added the #:format argument and effectively changed its default from 'ustar to 'pax.

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