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9.8 Other Stdio functions

The Stdio module also contains a collection of high level IO functions to make it easy to write short and readable Pike programs. Most of these functions are implemented using Stdio.File and Stdio.FILE.

FUNCTION: Stdio.append_path - append paths in a secure way
SYNTAX: string append_path(string absolute, string ... relative);
DESCRIPTION: Append relative paths to an absolute path and remove any "//", "../" or "/." to produce a straightforward absolute path as a result. "../" is ignorded in the relative paths if it makes the created path begin with something else than the absolute path (or so far created path).
EXAMPLE: > Stdio.append_path("/foo/bar/",".."); Result: /foo/bar/ > Stdio.append_path("/foo/bar/","../apa.c"); Result: /foo/bar/apa.c > Stdio.append_path("/foo/bar","./sune.c"); Result: /foo/bar/sune.c > Stdio.append_path("/foo/bar","bertil/../../sune.c"); Result: /foo/bar/sune.c > Stdio.append_path("/foo/bar","klas","bertil/../../sune.c"); Result: /foo/bar/klas/sune.c
SEE ALSO

FUNCTION: Stdio.file_size - return the size of a file in bytes
SYNTAX: int file_size(string file);
DESCRIPTION: Give the size of a file. Size -1 indicates that the file either does not exist, or that it is not readable by you. Size -2 indicates that it is a directory.
SEE ALSO

FUNCTION: Stdio.exist - check if a path exists
SYNTAX: int exist(string path);
DESCRIPTION: Returns true if the given path exists (is a directory or file), otherwise false.
SEE ALSO

FUNCTION: Stdio.is_dir - check if a path is a directory
SYNTAX: int is_dir(string path);
DESCRIPTION: Returns true if the given path is a directory, otherwise false.
SEE ALSO

FUNCTION: Stdio.is_file - check if a path is a file
SYNTAX: int is_file(string path);
DESCRIPTION: Returns true if the given path is a file, otherwise false.
SEE ALSO

FUNCTION: Stdio.is_link - check if a path is a symbolic link
SYNTAX: int is_link(string path);
DESCRIPTION: Returns true if the given path is a symbolic link, otherwise false.
SEE ALSO

FUNCTION: Stdio.mkdirhier - make a directory hierarchy
SYNTAX: int mkdirhier(string pathname, void|int mode);
DESCRIPTION: Creates zero or more directories to ensure that the given pathname is a directory. Returns zero if it fails and nonzero if it is successful. If a mode is given, it's used for the new directories after being &'ed with the current umask (on OS'es that supports this).
SEE ALSO

FUNCTION: Stdio.perror - print error
SYNTAX: void perror(string s);
DESCRIPTION: This function prints a message to stderr along with a description of what went wrong if available. It uses the system errno to find out what went wrong, so it is only applicable to IO errors.
SEE ALSO

FUNCTION: Stdio.read_bytes - read a number of bytes into a string from a file
SYNTAX: string read_bytes(string file,int start,int len); string read_bytes(string file,int start); string read_bytes(string file);
DESCRIPTION: Read len number of bytes from file file staring at byte start and return it as a string. If len is omitted, the rest of the file will be returned. If start is also omitted, the entire file will be returned.
SEE ALSO

FUNCTION: Stdio.read_file - read a number of lines into a string from file
SYNTAX: string read_file(string file, int start, int len); string read_file(string file);
DESCRIPTION: Read len lines from the file file after skipping start lines and return those lines as a string. If start and len are omitted the whole file is read.
SEE ALSO

FUNCTION: Stdio.readline - read a line from stdin
SYNTAX: string readline(string prompt);
DESCRIPTION: This function is gone. Use Stdio.Readline()->read instead.
SEE ALSO

FUNCTION: Stdio.recursive_rm - remove a file or a directory tree recursively
SYNTAX: int recursive_rm(string path);
DESCRIPTION: Remove a file or directory a directory tree, return 0 if it fails. Nonzero otherwise.
SEE ALSO

Stdio.sendfile - send contents from one file to another

object sendfile(array(string) headers, object from, int offset, int len, array(string) trailers, object to); or object sendfile(array(string) headers, object from, int offset, int len, array(string) trailers, object to, function(int, mixed ...:void) callback, mixed ... args);

DESCRIPTION

Sends headers followed by len bytes starting at offset from the file from followed by trailers to the file to. When completed callback is called with the total number of bytes sent as the first argument, followed by args.

Any of headers, from and trailers may be left out by setting them to 0.

Setting offset to -1 means send from the current position in from.

Setting len to -1 means send until from's end of file is reached.

The sending is performed asynchronously, and may complete before the function returns.

For callback to be called, the backend must be active (ie main() must have returned -1).

In some cases, the backend must also be active for any sending to be performed at all.

Stdio.File->set_nonblocking

FUNCTION: Stdio.werror - write to stderr
SYNTAX: void werror(string s);
DESCRIPTION: Writes a message to stderr. Stderr is normally the console, even if the process output has been redirected to a file or pipe.

FUNCTION: Stdio.write_file - append a string to a file
SYNTAX: int write_file(string file, string str)
DESCRIPTION: Append the string str onto the file file. Returns number of bytes written.
SEE ALSO

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