freopen

 

C

Lingua

Tipo di supporto

Gestione della memoria dinamica

La gestione degli errori

Programma di utilità

Data e ora utilità

Stringhe libreria

Algoritmi

Numeri

Ingresso / uscita supporto

Localizzazione supporto

Thread di supporto (C11)

Operazioni atomiche (C11)

 

File input/output

Funzioni Original: Functions The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
Accesso ai file Original: File access The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
fopen freopen fclose fflush	fwide setbuf setvbuf
Diretta input / output Original: Direct input/output The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
fread
fwrite
Ingresso formattato / uscita Original: Unformatted input/output The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
fgetc fgets fputc fputs getchar gets putchar puts ungetc	fgetwc fgetws fputwc fputws getwchar putwchar ungetwc
Formattato di input / output Original: Formatted input/output The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
scanf fscanf sscanf vscanf vfscanf vsscanf (C99) (C99) (C99) printf fprintf sprintf snprintf (C99) vprintf vfprintf vsprintf vsnprintf (C99)	wscanf fwscanf swscanf vwscanf vfwscanf vswscanf (C99) (C99) (C99) wprintf fwprintf swprintf vwprintf vfwprintf vswprintf
File di posizionamento Original: File positioning The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
ftell
fgetpos
fseek
fsetpos
rewind
La gestione degli errori Original: Error handling The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
clearerr
feof
ferror
perror
Le operazioni sui file Original: Operations on files The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
remove
rename
tmpfile
tmpnam

 

Defined in header <stdio.h>
FILE *freopen( const char *filename, const char *mode, FILE *stream );

Riassegna esistente stream flusso di file in un file diverso identificato da filenameusing modalità specificata. mode viene utilizzato per determinare la nuova modalità di accesso file.

Original:

Reassigns an existing file stream stream to a different file identified by filenameusing specified mode. mode is used to determine the new file access mode.

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Parametri

filename	-	il nome del file per associare il flusso di file Original: file name to associate the file stream to The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
mode	-	terminazione null stringa di caratteri determinazione nuova modalità di accesso ai file File access mode string Meaning Explanation Action if file already exists Action if file does not exist "r" read Open a file for reading read from start failure to open "w" write Create a file for writing destroy contents create new "a" append Append to a file write to end create new "r+" read extended Open a file for read/write read from start error "w+" write extended Create a file for read/write destroy contents create new "a+" append extended Open a file for read/write write to end create new File access mode flag "b" can optionally be specified to open a file in binary mode. This flag has effect only on Windows systems. On the append file access modes, data is written to the end of the file regardless of the current position of the file position indicator. Original: null-terminated character string determining new file access mode File access mode string Meaning Explanation Action if file already exists Action if file does not exist "r" read Open a file for reading read from start failure to open "w" write Create a file for writing destroy contents create new "a" append Append to a file write to end create new "r+" read extended Open a file for read/write read from start error "w+" write extended Create a file for read/write destroy contents create new "a+" append extended Open a file for read/write write to end create new File access mode flag "b" can optionally be specified to open a file in binary mode. This flag has effect only on Windows systems. On the append file access modes, data is written to the end of the file regardless of the current position of the file position indicator. The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
stream	-	il flusso di file da modificare Original: the file stream to modify The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.

Valore di ritorno

stream in caso di successo, NULL in caso di fallimento

Original:

stream on success, NULL on failure

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Esempio

Il seguente codice reindirizza stdout in un file

Original:

The following code redirects stdout to a file

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#include <stdio.h>
 
int main()
{
    printf("stdout is printed to console");
    freopen("redir.txt", "w", stdout);
    printf("Stdout is redirected to a file");
    fclose(stdout);
}

Output:

stdout is printed to console

Vedi anche

fopen	apre un file Original: opens a file The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (funzione)
fclose	chiude un file Original: closes a file The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (funzione)
C++ documentation for freopen