Re: input from STDIN or from a file

in reply to input from STDIN or from a file

I don't know how complex your program would be, but I usually just use,

$ cat file.txt
a
b
c

$ cat stdin.pl
#!/usr/bin/perl -l
while (<>) {
 $_ = uc;
 print;
}

$ perl stdin.pl file.txt
A
B
C

$ cat file.txt | perl stdin.pl
A
B
C
[download]

Or, just perl -lpe '$_=uc' if it's really that simple. Anyway, I don't see anything wrong with your code.

Update: Fixed missing -l (only the dash was there). Thanks almut :-)

Open source softwares? Share and enjoy. Make profit from them if you can. Yet, share and enjoy!

Comment on Re: input from STDIN or from a file Select or Download Code

Replies are listed 'Best First'.
Re^2: input from STDIN or from a file by almut (Canon) on Jan 28, 2008 at 19:17 UTC
`#!/usr/bin/perl - ^` [download] I'm not sure you want the dash at the end of the shebang line... It doesn't do any harm when invoking the code like you did, but when I try to run your sample code/data without explicitly calling perl (rather letting the OS handle the shebang), I'm getting `$ cat file.txt \| ./664708.pl Can't locate object method "a" via package "b" (perhaps you forgot to +load "b"?) at - line 1.` [download] I suppose this is because what comes in through stdin is being interpreted as Perl code, rather than as content to be read via `<>` ...	[reply] [d/l] [select]

Replies are listed 'Best First'.

Re^2: input from STDIN or from a file
by almut (Canon) on Jan 28, 2008 at 19:17 UTC

#!/usr/bin/perl -
                ^
[download]

I'm not sure you want the dash at the end of the shebang line...

It doesn't do any harm when invoking the code like you did, but when I try to run your sample code/data without explicitly calling perl (rather letting the OS handle the shebang), I'm getting

$ cat file.txt | ./664708.pl
Can't locate object method "a" via package "b" (perhaps you forgot to 
+load "b"?) at - line 1.
[download]

I suppose this is because what comes in through stdin is being interpreted as Perl code, rather than as content to be read via <> ...

[reply]
[d/l]
[select]

In Section Seekers of Perl Wisdom