12-08-2009
Confirmed
The "problem" with AIX utilities is that I can't "crack them open" short of using ProbeVue or truss. (You have no access to the source.) But I can say this: The information you speak of comes from two different calls. readdir() "scans" for all files in a directory, and stat() (or variant) gives the ls info.
If you do not need the ls information then the call to stat() would (should) never be made unless you are filtering on access time or something like that.
My recommendation is to capture stderr so you can avoid the ugliness you speak of. If the error message is mixed in stdout, it would be trivial to write your own version in C that does not (watch out for soft links if you do). Another option is to look at the -R option to ls, it may produce similar output but generate errors that are different (once again, provided that you are getting stuff that should be stderr in your stdout).
9 More Discussions You Might Find Interesting
1. Shell Programming and Scripting
Hi, first post, so hello to all.
I have a Bash scripting problem that is driving me a bit nutty.
It involves a program called 'convert' which is part of the ImageMagick collection.
Normal usage from the commandline is:
$ convert -resize 120x120 inputfile.jpg outputfile.jpg
This is... (7 Replies)
Discussion started by: andyj
7 Replies
2. Shell Programming and Scripting
i have a directory in which there are executable files and these files are added at runtime. now i need a shell script which will be called at a certain interval. this shell script should find the latest executable file in that directory and start that executable. care should be taken that once the... (6 Replies)
Discussion started by: kvineeth
6 Replies
3. Shell Programming and Scripting
Hi Guys,
I am writing a Unix script which accepts a directory path as parameter $1
so something like
/user5.data/WA/01
will be passed in.
I want to determine if the directory path passed in contains "WA" as above (because then I need to do something specific if it does)
What is the... (9 Replies)
Discussion started by: bcunney
9 Replies
4. Shell Programming and Scripting
Dear forum
I have the following small script:
#!/bin/ksh
echo -e "abba-o" | awk -F '-' '{ print $2 }' | cut -b 1It needs to be ksh.. in bash I don't have this problem.
If I run this on opensuse 10.2 I get this as output: e
If I run this on suse enterprise 10 sp2 then I get this: o
... (1 Reply)
Discussion started by: gemtry
1 Replies
5. Shell Programming and Scripting
Hey,
I have not posted here in a while. I have a biological data file that has 4 columns and I am interested in column 2. Column 5 contains a series of letters AGCT.
Basically the file looks something like this
Name AGGTTTTCCCCCCC L Q
Name1 AGGTTTTAAAAAACC L Q
Name2 ... (4 Replies)
Discussion started by: kylle345
4 Replies
6. Programming
Hi im very new to x86 programming and was wonder if there a function or ways to solve my problem. I believe the reason for my inaccurate result are from passing floating point number beyond what a SWORD could hold.
So far I been looking for a function that would allow me to round the floating... (1 Reply)
Discussion started by: godofdoom999
1 Replies
7. UNIX for Dummies Questions & Answers
Dear Members,
Depending on the current date i should find out the start and end dates of the quarter.
ex: Today date is 14-Nov-2011 then Quarter start date should be Oct 1 2011 and Quarter End date should be Dec 31 2011.
How can i do this?
Thanks
Sandeep (1 Reply)
Discussion started by: sandeep_1105
1 Replies
8. Shell Programming and Scripting
Please tell me how to write a bash script that asks the user to enter a word and that passes the entered word to a variable.
echo "Type a word and press the Enter key:"
myVar=`cat`
echo "You entered $myVar"
The above code is very awkward, because it requires the user to enter... (2 Replies)
Discussion started by: LessNux
2 Replies
9. Red Hat
How do I find the process ( which might got completed ) which were ran at specific time.
for e.g. I should be able to find below process after 2 hrs if I find by time 04:00
myuser 23285 22522 0 04:00 pts/0 00:00:00 /home/myuser/bin/abc.ksh (3 Replies)
Discussion started by: sameermohite
3 Replies
STDIN(3) BSD Library Functions Manual STDIN(3)
NAME
stdin, stdout, stderr -- standard I/O streams
SYNOPSIS
#include <stdio.h>
extern FILE *stdin;
extern FILE *stdout;
extern FILE *stderr;
DESCRIPTION
Under normal circumstances every Unix program has three streams opened for it when it starts up, one for input, one for output, and one for
printing diagnostic or error messages. These are typically attached to the user's terminal (see tty(4)) but might instead refer to files or
other devices, depending on what the parent process chose to set up. (See also the ``Redirection'' section of sh(1) .)
The input stream is referred to as ``standard input''; the output stream is referred to as ``standard output''; and the error stream is
referred to as ``standard error''. These terms are abbreviated to form the symbols used to refer to these files, namely stdin, stdout, and
stderr.
Each of these symbols is a stdio(3) macro of type pointer to FILE, and can be used with functions like fprintf(3) or fread(3).
Since FILEs are a buffering wrapper around Unix file descriptors, the same underlying files may also be accessed using the raw Unix file
interface, that is, the functions like read(2) and lseek(2). The integer file descriptors associated with the streams stdin, stdout, and
stderr are 0, 1, and 2, respectively. The preprocessor symbols STDIN_FILENO, STDOUT_FILENO, and STDERR_FILENO are defined with these values
in <unistd.h>.
Note that mixing use of FILEs and raw file descriptors can produce unexpected results and should generally be avoided. (For the masochistic
among you: POSIX.1, section 8.2.3, describes in detail how this interaction is supposed to work.) A general rule is that file descriptors
are handled in the kernel, while stdio is just a library. This means for example, that after an exec, the child inherits all open file
descriptors, but all old streams have become inaccessible.
Since the symbols stdin, stdout, and stderr are specified to be macros, assigning to them is non-portable. The standard streams can be made
to refer to different files with help of the library function freopen(3), specially introduced to make it possible to reassign stdin, stdout,
and stderr. The standard streams are closed by a call to exit(3) and by normal program termination.
SEE ALSO
sh(1), csh(1), open(2), fopen(3), stdio(3)
CONSIDERATIONS
The stream stderr is unbuffered. The stream stdout is line-buffered when it points to a terminal. Partial lines will not appear until
fflush(3) or exit(3) is called, or a newline is printed. This can produce unexpected results, especially with debugging output. The buffer-
ing mode of the standard streams (or any other stream) can be changed using the setbuf(3) or setvbuf(3) call. Note that in case stdin is
associated with a terminal, there may also be input buffering in the terminal driver, entirely unrelated to stdio buffering. (Indeed, nor-
mally terminal input is line buffered in the kernel.) This kernel input handling can be modified using calls like tcsetattr(3); see also
stty(1), and termios(3).
CONFORMING TO
The stdin, stdout, and stderr macros conform to ANSI X3.159-1989 (``ANSI C89''), and this standard also stipulates that these three streams
shall be open at program startup.
Linux 2.0 March 24, 1998 Linux 2.0