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Top Forums Programming forks, ipc, fifos, update issues... Post 84936 by linuxpenguin on Thursday 29th of September 2005 02:34:26 PM
Old 09-29-2005
Hi,
I am not getting a clear idea of what is happening.
Do you mean to say that the child part of fork is never executed?
or is it executed only once. Is show() by any chance using an exec function.

Please clarify the problem.
 

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Ns_Exec(3aolserver)					   AOLserver Library Procedures 				       Ns_Exec(3aolserver)

__________________________________________________________________________________________________________________________________________________

NAME
Ns_ExecArgblk, Ns_ExecArgv, Ns_ExecProc, Ns_ExecProcess, Ns_Fork, Ns_GetEnviron, Ns_WaitForProcess, Ns_WaitProcess, ns_fork - External process execution SYNOPSIS
#include "ns.h" int Ns_ExecArgblk(char *exec, char *dir, int fdin, int fdout, char *args, Ns_Set *env) int Ns_ExecArgv(char *exec, char *dir, int fdin, int fdout, char **argv, Ns_Set *env) int Ns_ExecProc(char *exec, char **argv) int Ns_ExecProcess(char *exec, char *dir, int fdin, int fdout, char *args, Ns_Set *env) int Ns_Fork(void) char **Ns_GetEnviron(void) int Ns_WaitForProcess(int pid, int *statusPtr) int Ns_WaitProcess(int pid) int ns_fork(void) _________________________________________________________________ DESCRIPTION
These functions handle fork and exec operations. See files: nsd/exec.c, nsd/tclenv.c and nsthread/fork.c. Ns_ExecArgblk(exec, dir, fdin, fdout, args, env) Executes a command in a child process. Return process id of child process exec'ing the command or -1 on failure. Provides extended error checking and error messages. Ns_ExecArgv(exec, dir, fdin, fdout, argv, env) Execute a command in a child process using fork(2) and execve(2), returns the process id of child process exec'ing the command or -1 on failure. The child sends an extended error message to the parent. Ns_ExecProc(exec, argv) Executes a command in a child process. Returns the process id of the child process exec'ing the command or -1 on failure. Simpli- fies call to Ns_ExecArgv. Ns_ExecProcess(exec, dir, fdin, fdout, args, env) Executes a command in a child process. Returns the process id of the child process exec'ing the command or -1 on failure. Calls Ns_ExecArgblk with same arguments. Ns_Fork() Posix style fork(), using fork1() on Solaris if needed. See fork(2) man page. Calls ns_fork. Ns_GetEnviron() Returns pointer to the environment vector. Ns_WaitForProcess(pid, statusPtr) Wait for child process. Returns NS_OK on success, or NS_ERROR on failure. *statusPtr is set to the exit code of the child process. Ns_WaitProcess(pid) Wait for child process. Calls Ns_WaitForProcess with NULL statusPtr. Returns NS_OK on success, or NS_ERROR on failure. ns_fork() Posix style fork(), using fork1() on Solaris if needed. SEE ALSO
nsd(1), info(n) KEYWORDS
AOLserver 4.0 Ns_Exec(3aolserver)
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