Read the main page on waitpid or wait to get more detail.
The return value of a process to the calling is process is the least significant eight bits of the number returned by main(). Which can be seen as signed or unsigned by the parent. So, the valid results from calling wait on a child returns values from 0 to 255 (looked at as unsigned).
By convention 0 means success, as defined in C by EXIT_SUCCESS.
Since main() is an int function you can return any valid int, but is not very useful to return numbers larger than the range I just defined.
Compile retval then run it with this script
And see what happens...
i just finished a project for a c++ class that i wrote at home on my computer, compiled with gcc. when i brought the code into school it would not compile, it would complain that cannot call main() function. at school we use ancient borland c++ from 1995. anyway my program has 20 different... (3 Replies)
What is the sytax to return an int from C program main back to calling shell?
#!/usr/bin/ksh
typeset -i NO_RECS
$NO_RECS=process_file
# Process file is a C program that is set up to return an int from main. The
#program complies with no issues, but an error is generated when the... (3 Replies)
Hi,
I have a main loop which calls a sub loop, which finally returns to the main loop itself. The main loop runs when a flag is set. Now, I have a signal handler for SIGINT, which resets the flag and thus stops the main loop. Suppose I send SIGINT while the program is in subloop, I get an error... (1 Reply)
Hi,
I am having issue with awk command . This command is running in the command prompt but inside a shell script.
awk -F'| ' 'int($1)==$1 && int($3) ==$3' int_check.txt
$cat int_check.txt
123|abc|123x
234|def|345
When i run it inside a shell script i am getting the error
"bailing... (5 Replies)
Hello, I have the below perl function int to return the integer value from the expression but it is not. I am not sure if something misses out here. Any help on this? Thanks in advance.
# Code sample Start
my $size = int (`1134 sample_text_here`);
print "$size \n";
# Code end
----------... (0 Replies)
Hi,
from the manual
listen(2): listen for connections on socket - Linux man page
It has a parameter called backlog and it limits the maximum length of queue of pending list.
If I set backlog to 128, is it means no more than 128 packets can be handled by server?
If I have three... (3 Replies)
Hi friends,
when I am passing arguments to main, I want another function to be able to have access to that function, the problem is that I am creating athread, which has a function like void *xyz(void *), how can pass the refernce of argv to this function, if you see my program, you will better... (2 Replies)
Hi. I have some code, that for some reason, I could not post it here in this post. Here's the address for it:
#if 0 shc Version 4.0.1, Generic Shell Script Compiler GNU GPL Version 3 Md - Pastebin.com
First off, I used "shc" to convert the code from shell script to C.
And The... (6 Replies)
Discussion started by: ignatius
6 Replies
LEARN ABOUT DEBIAN
pthread_exit
PTHREAD_EXIT(3) Linux Programmer's Manual PTHREAD_EXIT(3)NAME
pthread_exit - terminate calling thread
SYNOPSIS
#include <pthread.h>
void pthread_exit(void *retval);
Compile and link with -pthread.
DESCRIPTION
The pthread_exit() function terminates the calling thread and returns a value via retval that (if the thread is joinable) is available to
another thread in the same process that calls pthread_join(3).
Any clean-up handlers established by pthread_cleanup_push(3) that have not yet been popped, are popped (in the reverse of the order in
which they were pushed) and executed. If the thread has any thread-specific data, then, after the clean-up handlers have been executed,
the corresponding destructor functions are called, in an unspecified order.
When a thread terminates, process-shared resources (e.g., mutexes, condition variables, semaphores, and file descriptors) are not released,
and functions registered using atexit(3) are not called.
After the last thread in a process terminates, the process terminates as by calling exit(3) with an exit status of zero; thus, process-
shared resources are released and functions registered using atexit(3) are called.
RETURN VALUE
This function does not return to the caller.
ERRORS
This function always succeeds.
CONFORMING TO
POSIX.1-2001.
NOTES
Performing a return from the start function of any thread other than the main thread results in an implicit call to pthread_exit(), using
the function's return value as the thread's exit status.
To allow other threads to continue execution, the main thread should terminate by calling pthread_exit() rather than exit(3).
The value pointed to by retval should not be located on the calling thread's stack, since the contents of that stack are undefined after
the thread terminates.
BUGS
Currently, there are limitations in the kernel implementation logic for wait(2)ing on a stopped thread group with a dead thread group
leader. This can manifest in problems such as a locked terminal if a stop signal is sent to a foreground process whose thread group leader
has already called pthread_exit().
SEE ALSO pthread_create(3), pthread_join(3), pthreads(7)COLOPHON
This page is part of release 3.44 of the Linux man-pages project. A description of the project, and information about reporting bugs, can
be found at http://www.kernel.org/doc/man-pages/.
Linux 2009-03-30 PTHREAD_EXIT(3)