mirror of
https://github.com/fish-shell/fish-shell.git
synced 2024-11-27 03:13:37 +08:00
82 lines
2.1 KiB
C
82 lines
2.1 KiB
C
/** \file exec.h
|
|
Prototypes for functions for executing a program
|
|
*/
|
|
|
|
#ifndef FISH_EXEC_H
|
|
/**
|
|
Header guard
|
|
*/
|
|
#define FISH_EXEC_H
|
|
|
|
#include <wchar.h>
|
|
|
|
#include "proc.h"
|
|
#include "util.h"
|
|
|
|
/**
|
|
pipe redirection error message
|
|
*/
|
|
#define PIPE_ERROR L"An error occurred while setting up pipe"
|
|
|
|
/**
|
|
Initialize the exec library
|
|
*/
|
|
void exec_init();
|
|
|
|
/**
|
|
Destroy dynamically allocated data and other resources used by the
|
|
exec library
|
|
*/
|
|
void exec_destroy();
|
|
|
|
/**
|
|
Execute the processes specified by j.
|
|
|
|
I've put a fair bit of work into making builtins behave like other
|
|
programs as far as pipes are concerned. Unlike i.e. bash, builtins
|
|
can pipe to other builtins with arbitrary amounts of data, and so
|
|
on. To do this, after a builtin is run in the real process, it
|
|
forks and a dummy process is created, responsible for writing the
|
|
output of the builtin. This is surprisingly cheap on my computer,
|
|
probably because of the marvels of copy on write forking.
|
|
|
|
This rule is short circuted in the case where a builtin does not
|
|
output to a pipe and does in fact not output anything. The speed
|
|
improvement from this optimization is not noticable on a normal
|
|
computer/OS in regular use, but the promiscous amounts of forking
|
|
that resulted was responsible for a huge slowdown when using
|
|
Valgrind as well as when doing complex command-specific
|
|
completions.
|
|
|
|
|
|
*/
|
|
void exec( job_t *j );
|
|
|
|
/**
|
|
Evaluate the expression cmd in a subshell, add the outputs into the
|
|
list l. On return, the status flag as returned bu \c
|
|
proc_gfet_last_status will not be changed.
|
|
|
|
\param cmd the command to execute
|
|
\param l The list to insert output into.If \c l is zero, the output will be discarded.
|
|
|
|
\return the status of the last job to exit, or -1 if en error was encountered.
|
|
*/
|
|
int exec_subshell( const wchar_t *cmd,
|
|
array_list_t *l );
|
|
|
|
|
|
/**
|
|
Loops over close until thesyscall was run without beeing
|
|
interrupted. Thenremoves the fd from the open_fds list.
|
|
*/
|
|
void exec_close( int fd );
|
|
|
|
/**
|
|
Call pipe(), and add resulting fds to open_fds, the list of opend
|
|
file descriptors for pipes.
|
|
*/
|
|
int exec_pipe( int fd[2]);
|
|
|
|
#endif
|