pythonos結果
❶ python 使用 os.system() 時沒有返回正常的結果,返回了256 ubuntu16.04系統下 python版本 2.7.11
os.system方法返回的是系統程序執行後的返回值。這里256也許是有256項。
要獲得標准輸出stdout需要用子進程模塊subprocess,這是python3.x的做法。
2.7也許有類似吧.
❷ python os模塊怎麼使用
常用方法:
1. os.name——判斷現在正在實用的平台,Windows 返回 『nt'; linux 返回』posix'。
2. os.getcwd()——得到當前工作的目錄。
3. os.listdir()——指定所有目錄下所有的文件和目錄名。
例:
❸ python調用OS.system結束進程問題
os.system是執行命令,是否列印取決於命令是否有返回
如果你想不讓其列印 可以在命令中做手腳如: os.system('taskkill /IM dllhost.exe > NUL')
❹ python裡面怎麼將os.system的執行結果返回到變數
os.system(command)將返回系統執行command的結果,0為無錯誤。將其直接賦值給變數即可。
例如在Linux系統下執行輸出文件列表命令ls:
a = os.system('ls')
a的值為0,表明執行命令無錯誤。
{在Windows系統下,輸出文件列表命令為dir。}
❺ python3中,用os.system運行一個python2的程序(該程序調用一些模塊),結果好像是調用了python3模塊出錯
環境變數裡面設置的python3的路徑,所以os調用的時候啟動的python3,具體可以在命令行輸入python --version看下版本號
❻ windows python3 怎樣獲得os的返回值
解決:查閱了文檔發現os.system()的返回為:
On Unix, the return value is the exit status of the process encoded in the format specified for wait().
而os.wait()的返回為:
a 16-bit number, whose low byte is the signal number that killed the process, and whose high byte is the exit status (if the signal number
is zero);
os.system的返回值並不是執行程序的返回結果。而是一個16位的數,它的高位才是返回碼。也就是說os.system()返回256即 0×0100,返回碼應該是其高位0×01即1。所以要獲取程序運行退出的值(比如C的main函數中的return 0),需要處理一下。
ret = os.system('./a.out')
ret >>= 8
這樣才能獲取到正確的返回值。另外還要注意:python獲取到的值是無符號整數,所以返回負值的時候,列印出來是很大的正值。比如返回-1,python 會獲取到255,-2則254,以此類推。所以最好就判斷是否為0就可以了,實在要判斷自己寫的c程序返回值,建議返回0,1,2,3等值,出錯返回 -1。
另外,我遇到一次明明處理好了返回值,c程序調試信息提示也該返回值0了,結果python獲取到的是 -1,而且無論c程序返回多少,python都獲取-1。後來排查c程序的問題,發現原來是因為我這個python程序本身是由另一個C程序調用的,而調 用它的那個C程序中將SIGCLD信號忽略了(這表明python是根據子進程退出時產生的信號來獲取返回值的),我將那個C程序的SIGCLD綁定到函 數,即使那個函數什麼也不做,python也能獲取到正確的返回值了。
/**********************************************************************************************************************/
linux命令執行後無論成功與否都有一個返回值:
如果為 0,則表示命令執行成功,其它值則表示錯誤,具體的錯誤碼含義如下:
"OS error code 1: Operation not permitted"
"OS error code 2: No such file or directory"
"OS error code 3: No such process"
"OS error code 4: Interrupted system call"
"OS error code 5: Input/output error"
"OS error code 6: No such device or address"
"OS error code 7: Argument list too long"
"OS error code 8: Exec format error"
"OS error code 9: Bad file descriptor"
"OS error code 10: No child processes"
"OS error code 11: Resource temporarily unavailable"
"OS error code 12: Cannot allocate memory"
"OS error code 13: Permission denied"
"OS error code 14: Bad address"
"OS error code 15: Block device required"
"OS error code 16: Device or resource busy"
"OS error code 17: File exists"
"OS error code 18: Invalid cross-device link"
"OS error code 19: No such device"
"OS error code 20: Not a directory"
"OS error code 21: Is a directory"
"OS error code 22: Invalid argument"
"OS error code 23: Too many open files in system"
"OS error code 24: Too many open files"
"OS error code 25: Inappropriate ioctl for device"
"OS error code 26: Text file busy"
"OS error code 27: File too large"
"OS error code 28: No space left on device"
"OS error code 29: Illegal seek"
"OS error code 30: Read-only file system"
"OS error code 31: Too many links"
"OS error code 32: Broken pipe"
"OS error code 33: Numerical argument out of domain"
"OS error code 34: Numerical result out of range"
"OS error code 35: Resource deadlock avoided"
"OS error code 36: File name too long"
"OS error code 37: No locks available"
"OS error code 38: Function not implemented"
"OS error code 39: Directory not empty"
"OS error code 40: Too many levels of symbolic links"
"OS error code 42: No message of desired type"
"OS error code 43: Identifier removed"
"OS error code 44: Channel number out of range"
"OS error code 45: Level 2 not synchronized"
"OS error code 46: Level 3 halted"
"OS error code 47: Level 3 reset"
"OS error code 48: Link number out of range"
"OS error code 49: Protocol driver not attached"
"OS error code 50: No CSI structure available"
"OS error code 51: Level 2 halted"
"OS error code 52: Invalid exchange"
"OS error code 53: Invalid request descriptor"
"OS error code 54: Exchange full"
"OS error code 55: No anode"
"OS error code 56: Invalid request code"
"OS error code 57: Invalid slot"
"OS error code 59: Bad font file format"
"OS error code 60: Device not a stream"
"OS error code 61: No data available"
"OS error code 62: Timer expired"
"OS error code 63: Out of streams resources"
"OS error code 64: Machine is not on the network"
"OS error code 65: Package not installed"
"OS error code 66: Object is remote"
"OS error code 67: Link has been severed"
"OS error code 68: Advertise error"
"OS error code 69: Srmount error"
"OS error code 70: Communication error on send"
"OS error code 71: Protocol error"
"OS error code 72: Multihop attempted"
"OS error code 73: RFS specific error"
"OS error code 74: Bad message"
"OS error code 75: Value too large for defined data type"
"OS error code 76: Name not unique on network"
"OS error code 77: File descriptor in bad state"
"OS error code 78: Remote address changed"
"OS error code 79: Can not access a needed shared library"
"OS error code 80: Accessing a corrupted shared library"
"OS error code 81: .lib section in a.out corrupted"
"OS error code 82: Attempting to link in too many shared libraries"
"OS error code 83: Cannot exec a shared library directly"
"OS error code 84: Invalid or incomplete multibyte or wide character"
"OS error code 85: Interrupted system call should be restarted"
"OS error code 86: Streams pipe error"
"OS error code 87: Too many users"
"OS error code 88: Socket operation on non-socket"
"OS error code 89: Destination address required"
"OS error code 90: Message too long"
"OS error code 91: Protocol wrong type for socket"
"OS error code 92: Protocol not available"
"OS error code 93: Protocol not supported"
"OS error code 94: Socket type not supported"
"OS error code 95: Operation not supported"
"OS error code 96: Protocol family not supported"
"OS error code 97: Address family not supported by protocol"
"OS error code 98: Address already in use"
"OS error code 99: Cannot assign requested address"
"OS error code 100: Network is down"
"OS error code 101: Network is unreachable"
"OS error code 102: Network dropped connection on reset"
"OS error code 103: Software caused connection abort"
"OS error code 104: Connection reset by peer"
"OS error code 105: No buffer space available"
"OS error code 106: Transport endpoint is already connected"
"OS error code 107: Transport endpoint is not connected"
"OS error code 108: Cannot send after transport endpoint shutdown"
"OS error code 109: Too many references: cannot splice"
"OS error code 110: Connection timed out"
"OS error code 111: Connection refused"
"OS error code 112: Host is down"
"OS error code 113: No route to host"
"OS error code 114: Operation already in progress"
"OS error code 115: Operation now in progress"
"OS error code 116: Stale NFS file handle"
"OS error code 117: Structure needs cleaning"
"OS error code 118: Not a XENIX named type file"
"OS error code 119: No XENIX semaphores available"
"OS error code 120: Is a named type file"
"OS error code 121: Remote I/O error"
"OS error code 122: Disk quota exceeded"
"OS error code 123: No medium found"
"OS error code 124: Wrong medium type"
"OS error code 125: Operation canceled"
"OS error code 126: Required key not available"
"OS error code 127: Key has expired"
"OS error code 128: Key has been revoked"
"OS error code 129: Key was rejected by service"
"OS error code 130: Owner died"
"OS error code 131: State not recoverable"
❼ python,os.popen 打包後出現問題
你打包成exe後,命令行應該是pyinstller -Fw xxx.py
你加上了w參數也就是把console設置成了flase;那麼os.popen()或者subprocess.popen()執行的時候沒有載體,你只有把console設置成true,也就是命令改為pyinstaller -F xxx.py,這樣你的os.popen()可執行,也能獲得返回值。
❽ python函數里調用os模塊中的內容結果顯示未定義
你的問題很奇怪,我的都可以通過
❾ python調用另外一個python程序的結果
os.system只是運行,不返回結果。
用commands
import commands
txt = commands.getoutput('ls -al')
❿ python模塊os裡面os.system命令返回什麼
linux命令都是返回0代表成果,這是一個習慣,基本沒有人用返回值0代表命令失敗.
所以 os.system(命令) 如果返回為0則帶便命令執行成功了.
具體返回其他數值代表什麼意思,就要看具體命令是什麼了.比如最常用的 ls 命令, 有三個返回值:
0 代表成功
1 代表小問題
2 代表大問題