Login or Register to Ask a Question and Join Our Community

Sponsored Content
Full Discussion: c++ calling main() function
Top Forums Programming c++ calling main() function Post 33888 by Perderabo on Wednesday 22nd of January 2003 07:28:46 PM
Old 01-22-2003
That would just be more of the same. Anything with the potential to result in an unlimited depth of function calls will eventually exhaust resources or consume far too many resources.

Ideally the each function should simply return when they are done. And the main function should simply have a loop that displays the menu and calls the proper function. This is the structured way and it's the only way I program.

But lots of people disagree with me (including such people as Richard Stevens and Dennis Ritchie). So I should tell you that there is also setjmp()/longjmp(). You call setjmp at some point in your program...like just before you print the main menu. Later, even in some other function, you call longjmp. And then the next thing that happens is that you're back right after the setjmp and stack pointer is magically unwound as well. This will not leak memory.

A third technique is to re-exec the program. I think that this is pathetic and here I can claim broad support.
 

10 More Discussions You Might Find Interesting

1. Shell Programming and Scripting

Calling subscript but sleep halts the main script

Ok, I have written a main script which checks a directory contents every 30 secs then sleeps. The subscript does a usermod, if the user is logged on, it sleeps for 30 secs and then trys again over and over again. Here's the problem. when the subscript is called ./subscript.sh or exec... (1 Reply)
Discussion started by: doublejz
1 Replies

2. Programming

Return value (int) from main to calling shell

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)
Discussion started by: flounder
3 Replies

3. Programming

main function

Is it possible to execute any function before main() function in C or C++. (6 Replies)
Discussion started by: arun.viswanath
6 Replies

4. Shell Programming and Scripting

Return a value from called function to the calling function

I have two scripts. script1.sh looks -------------------------------- #!/bin/bash display() { echo "Welcome to Unix" } display ----------------------------- Script2.sh #!/bin/bash sh script1.sh //simply calling script1.sh ------------------------------ (1 Reply)
Discussion started by: mvictorvijayan
1 Replies

5. Shell Programming and Scripting

SHELL SCRIPT Function Calling Another Function Please Help...

This is my function which is creating three variables based on counter & writing these variable to database by calling another function writeRecord but only one record is getting wrote in DB.... Please advise ASAP...:confused: function InsertFtg { FTGSTR="" echo "Saurabh is GREAT $#" let... (2 Replies)
Discussion started by: omkar.sonawane
2 Replies

6. UNIX for Dummies Questions & Answers

calling process and going back to the main loop

hi everyone , i want to read an option and depending on the option call the program .For ex #! /bin/ksh export JAVA_HOME=/home/oracle/jdk1.6.0_20 echo " Please enter mod-modeler, dev - sqldeveloper" read choice if ; then echo ' SQL DEVELOPER IS STARTING NOW ... ' cd... (0 Replies)
Discussion started by: kdev
0 Replies

7. Shell Programming and Scripting

main program is not calling small other programs

I am trying to understand a program in a book and this program suppose to call other programs which are in the same folder, the other programs are called 'lu' and 'add' but for some reason when it gets to the last line of each case to call these programs there is an error message saying ./rolo:... (2 Replies)
Discussion started by: bartsimpsong
2 Replies

8. Programming

Function main returning int?

H friends, As we know, a function returns a value and that value is saved somwhere. like int Sum( int x, int y ) { return x + y; } Total = Sum( 10, 20 ); The value 30 is saved in variable Total. Now the question is, what int value does the function main return, and where is it... (5 Replies)
Discussion started by: gabam
5 Replies

9. AIX

Calling functions from main program from dlopened library function

Hello All, I am trying to call a function from the calling main program from a dlopened library function, below is the entire code, when I execute it it crashes with sigill. Can you guys help me out I guess I am missing out on the linker flag or something here. besides I am new to AIX and... (1 Reply)
Discussion started by: syedtoah
1 Replies

10. Shell Programming and Scripting

Help to Modify File Name in each function before calling another function.

I have a script which does gunzip, zip and untar. Input to the script is file name and file directory (where file is located) I am reading the input parameters as follows: FILENAME=$1 FILEDIR=$2 I have created 3 functions that are as follows: 1) gunzip file 2) unzip file... (2 Replies)
Discussion started by: pinnacle
2 Replies

LEARN ABOUT REDHAT

longjmp

LONGJMP(3)							 Library functions							LONGJMP(3)

NAME

       longjmp, siglongjmp - non-local jump to a saved stack context

SYNOPSIS

       #include <setjmp.h>

       void longjmp(jmp_buf env, int val);
       void siglongjmp(sigjmp_buf env, int val);

DESCRIPTION

       longjmp()  and  setjmp()  are  useful for dealing with errors and interrupts encountered in a low-level subroutine of a program.  longjmp()
       restores the environment saved by the last call of setjmp() with the corresponding env argument.  After	longjmp()  is  completed,  program
       execution continues as if the corresponding call of setjmp() had just returned the value val.  longjmp() cannot cause 0 to be returned.	If
       longjmp is invoked with a second argument of 0, 1 will be returned instead.

       siglongjmp() is similar to longjmp() except for the type of its env argument.  If the sigsetjmp() call that set this  env  used	a  nonzero
       savesigs flag, siglongjmp() also restores the set of blocked signals.

RETURN VALUE

       These functions never return.

CONFORMING TO

       POSIX

NOTES

       POSIX does not specify whether longjmp will restore the signal context.	If you want to save and restore signal masks, use siglongjmp.

       longjmp() and siglongjmp() make programs hard to understand and maintain.  If possible an alternative should be used.

SEE ALSO

       setjmp(3), sigsetjmp(3)

								    1997-03-02								LONGJMP(3)
All times are GMT -4. The time now is 10:54 AM.
Unix & Linux Forums Content Copyright 1993-2022. All Rights Reserved.
Privacy Policy