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Full Discussion: How this works?
Top Forums UNIX for Advanced & Expert Users How this works? Post 302449629 by jlliagre on Tuesday 31st of August 2010 04:46:31 AM
Old 08-31-2010
No fork in unistd ?
Code:
$ grep -w fork /usr/include/unistd.h
extern pid_t fork(void);
extern pid_t fork();

 

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getpid(2)							   System Calls 							 getpid(2)

NAME
getpid, getpgrp, getppid, getpgid - get process, process group, and parent process IDs SYNOPSIS
#include <unistd.h> pid_t getpid(void); pid_t getpgrp(void); pid_t getppid(void); pid_t getpgid(pid_t pid); DESCRIPTION
The getpid() function returns the process ID of the calling process. The getpgrp() function returns the process group ID of the calling process. The getppid() function returns the parent process ID of the calling process. The getpgid() function returns the process group ID of the process whose process ID is equal to pid, or the process group ID of the calling process, if pid is equal to 0. RETURN VALUES
Upon successful completion, these functions return the process group ID. Otherwise, getpgid() returns (pid_t)-1 and sets errno to indicate the error. ERRORS
The getpgid() function will fail if: EPERM The process whose process ID is equal to pid is not in the same session as the calling process, and the implementation does not allow access to the process group ID of that process from the calling process. ESRCH There is no process with a process ID equal to pid. The getpgid() function may fail if: EINVAL The value of the pid argument is invalid. ATTRIBUTES
See attributes(5) for descriptions of the following attributes: +-----------------------------+-----------------------------+ | ATTRIBUTE TYPE | ATTRIBUTE VALUE | +-----------------------------+-----------------------------+ |Interface Stability |Standard | +-----------------------------+-----------------------------+ |MT-Level |Async-Signal-Safe | +-----------------------------+-----------------------------+ SEE ALSO
intro(2), exec(2), fork(2), getsid(2), setpgid(2), setpgrp(2), setsid(2), signal(3C), attributes(5), standards(5) SunOS 5.10 28 Dec 1996 getpid(2)
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