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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.
 +   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)