Re^2: printing of an array

check out the man page called "perlfunc", it describes all of perl's functions and what they do. if you are running on a shell that lets you create aliases or functions (like bash), a good alias is:

alias perlfunc='perldoc -f'
# or as a function:
function perlfunc {
    local func=${1:?"Need a function name"}
    perldoc "$1"
}
# add one of the above to your ".bashrc...
[download]

Then you can just type the name of the function:

> perlfunc print
KFPMKBZGPT(1)         User Contributed Perl Documentation        KFPMK
+BZGPT(1)



       print FILEHANDLE LIST
       print FILEHANDLE
       print LIST
       print   Prints a string or a list of strings.  Returns true if
               successful.
....
               Printing to a closed pipe or socket will generate a SIG
+PIPE
               signal.  See perlipc for more on signal handling.



perl v5.16.2                      2013-03-10                     KFPMK
+BZGPT(1)
[download]

Note, the above is not the whole entry (it's a page long, but will tell you exactly what it does...

if you have your documentation installed as 'manpages',

man perlfunc
[download]

will show you the whole list. (it's *way* long...)

Hope that helps...

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Re^3: printing of an array by manishrathi (Beadle) on Mar 11, 2013 at 02:37 UTC
`$filelist = "C:\Users\cign\Desktop\printFile.txt"; my @files = (file1, file2, file3); open(WRITEFILE, ">$filelist") \|\| die("ERROR: unable to open file \n") +; select WRITEFILE; foreach my $file (@files){ print WRITEFILE ; #"$file\n"; } close WRITEFILE;` [download] I tried running above code, but I am getting error message unable to open file. WHats wrong in here, why can this file handle not open ?	[reply] [d/l]
Re^4: printing of an array by AnomalousMonk (Archbishop) on Mar 11, 2013 at 04:15 UTC
WHats wrong in here, why can this file handle not open ? It's good that you are checking the success of the open function call and calling die if it fails. The answer to the question "why?" is contained in the `$!` error variable (see perlvar, especially the discussion in Error Variables). Put that in your `die` function and see the result: `open(WRITEFILE, ">$filelist") \|\| die("ERROR: unable to open file: $! \n");` In addition, the statement `my @files = (file1, file2, file3);` suggests you are not using warnings and strict at the beginning of your code: `use warnings;` `use strict;` I strongly suggest you do so. Furthermore, the statement `$filelist = "C:\Users\cign\Desktop\printFile.txt";` is highly suspect. Add a print statement for `$filelist` immediately after this assignment and check if what is printed is what you expect. The other tactic is to include the filename in delimiters in the die call discussed above: `open(WRITEFILE, ">$filelist") \|\| die("opening '$filelist': $!\n");` The next step is to use the three-argument form of `open`: `open my $writefile, '>', $filelist or die "opening '$filelist': $!"`	[reply] [d/l] [select]
Re^4: printing of an array by perl-diddler (Chaplain) on Mar 31, 2013 at 04:38 UTC
What's wrong is the way you are entering the file name. Double quotes allow interpretation of what is between them: I.e. step 1: print out the name of the file: `perl -e ' use P; my $filelist="C:\Users\cign\Desktop\printFile.txt"; P "opening file: %s", $filelist; ' opening file: C:SERS GNDESKTOPPRINTFILE.TXT` [download] Is that the file you wanted to open? Prolly not. step 2, at least turn on warning and try to use strict - they detect alot (though not all) of problems -- in this case they would have given you a hint: `perl -we 'use strict; use P; my $filelist="C:\Users\cign\Desktop\printFile.txt"; P "opening file: %s", $filelist;' Unrecognized escape \D passed through at -e line 2. Unrecognized escape \p passed through at -e line 2. opening file: C:SERS GNDESKTOPPRINTFILE.TXT` [download] use single quotes to define a literal, or put another backslash \ before each \, or use the 'q{...}' operator to really set it off that emphasizes it has to be taken literally (and doesn't interfere with my using single quotes in a 1 line program I typed in on the command line! ;-) perl -we 'use strict; use P; my $filelist=q{C:\Users\cign\Desktop\printFile.txt}; P "opening file: %s", $filelist;' opening file: C:\Users\cign\Desktop\printFile.txt ## #alternate ways ## > perl -we 'use strict; use P; my $filelist='\''C:\Users\cign\Desktop\printFile.txt'\''; P "opening file: %s", $filelist;' opening file: C:\Users\cign\Desktop\printFile.txt ## > perl -we 'use strict; use P; my $filelist="C:\\Users\\cign\\Desktop\\printFile.txt"; P "opening file: %s", $filelist;' opening file: C:\Users\cign\Desktop\printFile.txt ### ## my favorite (in a file)... #! perl/bin/perl.exe use strict; use P; my $filelist="C:/Users/../tmp/../Perl64/printFile.txt"; P "opening file: %s", $filelist; open (test, ">", $filelist) or die "didn't work"; print test "Hello World!\n"; close test; C:\Perl64>perl test.pl opening file: C:/Users/../tmp/../Perl64/printFile.txt C:\Perl64>type printFile.txt Hello World! [download] Forward slash works in alot of places on Windows cuz the underlying 'NT' OS accepts it.	[reply] [d/l] [select]