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|
{
"metadata": {
"name": "chapter-20.ipynb"
},
"nbformat": 3,
"nbformat_minor": 0,
"worksheets": [
{
"cells": [
{
"cell_type": "markdown",
"metadata": {},
"source": [
"<h1>Chapter 20: C Under Linux <h1>"
]
},
{
"cell_type": "markdown",
"metadata": {},
"source": [
"<h3>Fork , Page number: 655<h3>"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"\n",
"import os\n",
"\n",
"print \"Before Forking\" \n",
"child = os.fork() #create a child process\n",
"print \"After Forking\\n\" \n",
"\n"
],
"language": "python",
"metadata": {},
"outputs": [],
"prompt_number": 7
},
{
"cell_type": "markdown",
"metadata": {},
"source": [
"<h3>Creating a Child Process , Page number: 656<h3>"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"\n",
"import os\n",
"\n",
"pid = os.fork()\n",
"if pid == 0:\n",
" print \"In child process\" # code to play animated GIF file\n",
"else:\n",
" print \"In parent process\" #code to copy file \n",
" \n"
],
"language": "python",
"metadata": {},
"outputs": []
},
{
"cell_type": "markdown",
"metadata": {},
"source": [
"<h3>PID of Parent And Child Processes , Page number: 657<h3>"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"\n",
"import os\n",
"from multiprocessing import Process\n",
"\n",
"if __name__ == '__main__':\n",
" ppid=os.getpid()\n",
" p = Process()\n",
" p.start()\n",
" cid = os.getpid()\n",
" \n",
"\n",
"if (cid):\n",
" print (\"Child : Hello I am the child process\")\n",
" print (\"Child : Child\u2019s PID: \", os.getpid( ) )\n",
" print (\"Child : Parent\u2019s PID: \", os.getppid( ) )\n",
"else:\n",
" print (\"Parent : Hello I am the parent process\" )\n",
" print (\"Parent : Parent\u2019s PID: \", os.getpid( ) )\n",
" print (\"Parent : Child\u2019s PID: \", cid )\n",
"\n",
"\n",
"\n"
],
"language": "python",
"metadata": {},
"outputs": []
},
{
"cell_type": "markdown",
"metadata": {},
"source": [
"<h3>Execl , Page number: 659<h3>"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"\n",
"import os\n",
"\n",
"\n",
"pid = os.fork()\n",
"if pid == 0:\n",
" os.execl ( \"/bin/ls\",\"-al\", \"/etc\", NULL ) \n",
" print \"Child: After exec( )\"\n",
"else:\n",
" print \"Parent process\""
],
"language": "python",
"metadata": {},
"outputs": [],
"prompt_number": "*"
},
{
"cell_type": "markdown",
"metadata": {},
"source": [
"<h3>Waitpid , Page number: 662<h3>"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"\n",
"import os\n",
"\n",
"i = 0 \n",
"pid = os.fork( ) \n",
"if ( pid == 0 ):\n",
" while ( i < 4294967295 ):\n",
" i=i+1\n",
" print \"The child is now terminating\" \n",
"else:\n",
" os.waitpid ( pid, status, 0 )\n",
" if ( os.WIFEXITED ( status ) ):\n",
" print \"Parent: Child terminated normally\" \n",
" else:\n",
" print \"Parent: Child terminated abnormally\" \n"
],
"language": "python",
"metadata": {},
"outputs": [],
"prompt_number": "*"
},
{
"cell_type": "code",
"collapsed": false,
"input": [],
"language": "python",
"metadata": {},
"outputs": []
}
],
"metadata": {}
}
]
}
|
