05-09-2010
10 More Discussions You Might Find Interesting
1. Programming
I have a program which I wish to modify. It used to be run from the command line, but now I wish to change this so it can be used as a function.
The program has complex argument processing so I want to pass my paramters to as if it were being called by the OS as a program.
I have tried to... (2 Replies)
Discussion started by: mbb
2 Replies
2. Programming
I searched on the forums. No advises.
I am using a previous source code. I changed the main function main(int argc, char **argv) in a function misc(int argc, char **argv). How do you use the argc and argv parameters? This is how I am calling the function :
char param;
strcat(param,"wgrib ");... (4 Replies)
Discussion started by: Akeson Chihiro
4 Replies
3. Shell Programming and Scripting
I have a script that asks a bunch of questions using the following method for input:
print "Name:";
while(<>){
chomp;
$name=$_;
}
So for example, if the questions asked for name, age, & color (in that order)... I want to be able to easily convert $ARGV into the input expected by... (2 Replies)
Discussion started by: jjinno
2 Replies
4. Programming
Hi C experts,
I have the following code for adding command line option for a program
int main (argc, argv)
int argc;
char *argv;
{
char *mem_type; //memory type
char *name; //name of the memory
int addr; //address bits
int data; ... (5 Replies)
Discussion started by: return_user
5 Replies
5. Shell Programming and Scripting
this is in one of my scripts...
if ($#argv == 0) then
echo 'blah bla'
exit 0
endif
I want it to be something like this...
if ($#argv == 0 OR $argv >=3)
echo 'blah bla'
exit 0
endif
so when the arguments are none, or greater than three I want this "if then" to take over. how? I... (5 Replies)
Discussion started by: ajp7701
5 Replies
6. Shell Programming and Scripting
Hello all,
Had a quick question:
In a typical csh script should inputting via stdin (i.e. set i = $< ) increase the value of $#argv ?
echo enter an value:
set val= "$<"
if($#argv == 0) then
echo No args
else
echo The arg is $argv
so if a value is inputted #argv... (1 Reply)
Discussion started by: new2C
1 Replies
7. Programming
when i run my program, i have a parameter, that i want to set the value to another string
i am using
int main(int argc, char **argv) {
char my_str=argv;
printf("%s",my_str);
return 0;
}
and i get
Segmentation fault
ran using
./my_prog /usr/share/dict/words hello1
... (2 Replies)
Discussion started by: omega666
2 Replies
8. Programming
I'm working on my own pow function and I need to make a copy of *argv but
I think that I am having trouble with the size of *argv and the size of any array that I
make. The code below isn't working for me. and I want to accept any number no
matter the size with pow -f 2 2. I was working out... (16 Replies)
Discussion started by: Errigour
16 Replies
9. UNIX for Advanced & Expert Users
All of my machines (various open source derivatives on x86 and amd64) store argv above the stack (at a higher memory address). I am curious to learn if any systems store argv below the stack (at a lower memory address).
I am particularly interested in proprietary Unices, such as Solaris, HP-UX,... (9 Replies)
Discussion started by: alister
9 Replies
10. UNIX for Dummies Questions & Answers
So i am trying to read in file
readFile <GivenFile> modFile
looking for a regular file under the directories in the GivenFile and print them out is my over all goal.
basically I am looking for anything that looks like a directory in the given file and printing it out.
Since I am trying to do... (2 Replies)
Discussion started by: squidGreen
2 Replies
LEARN ABOUT MINIX
readdir_r
READDIR_R(3) Linux Programmer's Manual READDIR_R(3)
NAME
readdir_r - read a directory
SYNOPSIS
#include <dirent.h>
int readdir_r(DIR *dirp, struct dirent *entry, struct dirent **result);
Feature Test Macro Requirements for glibc (see feature_test_macros(7)):
readdir_r():
_POSIX_C_SOURCE
|| /* Glibc versions <= 2.19: */ _BSD_SOURCE || _SVID_SOURCE
DESCRIPTION
This function is deprecated; use readdir(3) instead.
The readdir_r() function was invented as a reentrant version of readdir(3). It reads the next directory entry from the directory stream
dirp, and returns it in the caller-allocated buffer pointed to by entry. For details of the dirent structure, see readdir(3).
A pointer to the returned buffer is placed in *result; if the end of the directory stream was encountered, then NULL is instead returned in
*result.
It is recommended that applications use readdir(3) instead of readdir_r(). Furthermore, since version 2.24, glibc deprecates readdir_r().
The reasons are as follows:
* On systems where NAME_MAX is undefined, calling readdir_r() may be unsafe because the interface does not allow the caller to specify the
length of the buffer used for the returned directory entry.
* On some systems, readdir_r() can't read directory entries with very long names. When the glibc implementation encounters such a name,
readdir_r() fails with the error ENAMETOOLONG after the final directory entry has been read. On some other systems, readdir_r() may
return a success status, but the returned d_name field may not be null terminated or may be truncated.
* In the current POSIX.1 specification (POSIX.1-2008), readdir(3) is not required to be thread-safe. However, in modern implementations
(including the glibc implementation), concurrent calls to readdir(3) that specify different directory streams are thread-safe. There-
fore, the use of readdir_r() is generally unnecessary in multithreaded programs. In cases where multiple threads must read from the
same directory stream, using readdir(3) with external synchronization is still preferable to the use of readdir_r(), for the reasons
given in the points above.
* It is expected that a future version of POSIX.1 will make readdir_r() obsolete, and require that readdir(3) be thread-safe when concur-
rently employed on different directory streams.
RETURN VALUE
The readdir_r() function returns 0 on success. On error, it returns a positive error number (listed under ERRORS). If the end of the
directory stream is reached, readdir_r() returns 0, and returns NULL in *result.
ERRORS
EBADF Invalid directory stream descriptor dirp.
ENAMETOOLONG
A directory entry whose name was too long to be read was encountered.
ATTRIBUTES
For an explanation of the terms used in this section, see attributes(7).
+------------+---------------+---------+
|Interface | Attribute | Value |
+------------+---------------+---------+
|readdir_r() | Thread safety | MT-Safe |
+------------+---------------+---------+
CONFORMING TO
POSIX.1-2001, POSIX.1-2008.
SEE ALSO
readdir(3)
COLOPHON
This page is part of release 4.15 of the Linux man-pages project. A description of the project, information about reporting bugs, and the
latest version of this page, can be found at https://www.kernel.org/doc/man-pages/.
2016-03-01 READDIR_R(3)