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fexist [2008/05/28 19:46] (current)
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 +# $EPIC: fexist.txt,​v 1.4 2008/05/28 19:46:15 jnelson Exp $
 +======Synopsis:​======
 +$__fexist__(%%<​file>​%%) \\ 
 +$__fexist__(%%""​ <​file>​%%)
 +
 +======Technical:​======
 +   * The %%<​file>​%% argument is a [[what is a word|dword]] which is different from most function arguments.
 +   * In the first case, %%<​file>​%% is a single extended word (you may surround it with double quotes if it contains spaces). ​ Any further arguments are ignored.
 +   * In the second case, the first argument is an empty string, and the rest of the arguments are taken as a filename literally. ​ Do not backslash or double quote anything in%% <​file>​%%.
 +   * Tilde-expansion is supported in both forms, both "​~/​file"​ for files in your home directory and "​~user/​file"​ for files in someone else's home directory.
 +   * If %%<​file>​%% is not a symbolic link, it exists, and you have read access to it, the return value is 1.
 +   * If %%<​file>​%% is a symbolic link and the file it points to exists, and you have read access to it, the return value is 1.
 +   * In the other cases (the file doesn'​t exist, or you can't read it), the return value is -1.
 +
 +======Practical:​======
 +This function is used when you want to see if a particular file exists.
 +This could be useful to make sure a file is present before trying to
 +load it.  This function does not return 0!
 +
 +======Returns:​======
 +<​file>​
 +-1   file does not exist or is not readable by you.
 + ​1 ​  file exists and you can read it.
 +</​file>​
 +
 +======Examples:​======
 +<​file>​
 +$fexist(/​etc/​passwd) ​                  ​probably will return 1
 +$fexist(~/​.ircrc) ​                     probably will return 1 too
 +$fexist(fake_file) ​                    ​returns -1
 +</​file>​
 +
 +======History:​======
 +This function first appeared in EPIC3pre7.
  
fexist.txt ยท Last modified: 2008/05/28 19:46 (external edit)