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fscanf

(PHP 4 >= 4.0.1, PHP 5, PHP 7, PHP 8)

fscanfParses input from a file according to a format

Description

fscanf(resource $stream, string $format, mixed &...$vars): array|int|false|null

The function fscanf() is similar to sscanf(), but it takes its input from a file associated with stream and interprets the input according to the specified format.

Any whitespace in the format string matches any whitespace in the input stream. This means that even a tab (\t) in the format string can match a single space character in the input stream.

Each call to fscanf() reads one line from the file.

Parameters

stream

A file system pointer resource that is typically created using fopen().

format

The interpreted format for string, which is described in the documentation for sprintf() with following differences:

  • Function is not locale-aware.
  • F, g, G and b are not supported.
  • D stands for decimal number.
  • i stands for integer with base detection.
  • n stands for number of characters processed so far.
  • s stops reading at any whitespace character.
  • * instead of argnum$ suppresses the assignment of this conversion specification.

vars

The optional assigned values.

Return Values

If only two parameters were passed to this function, the values parsed will be returned as an array. Otherwise, if optional parameters are passed, the function will return the number of assigned values. The optional parameters must be passed by reference.

If there are more substrings expected in the format than there are available within string, null will be returned. On other errors, false will be returned.

Examples

Example #1 fscanf() Example

<?php
$handle
= fopen("users.txt", "r");
while (
$userinfo = fscanf($handle, "%s\t%s\t%s\n")) {
list (
$name, $profession, $countrycode) = $userinfo;
//... do something with the values
}
fclose($handle);
?>

Example #2 Contents of users.txt

javier  argonaut        pe
hiroshi sculptor        jp
robert  slacker us
luigi   florist it

See Also

  • fread() - Binary-safe file read
  • fgets() - Gets line from file pointer
  • fgetss() - Gets line from file pointer and strip HTML tags
  • sscanf() - Parses input from a string according to a format
  • printf() - Output a formatted string
  • sprintf() - Return a formatted string

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User Contributed Notes 7 notes

up
18
yasuo_ohgaki at hotmail dot com
23 years ago
For C/C++ programmers.

fscanf() does not work like C/C++, because PHP's fscanf() move file pointer the next line implicitly.
up
7
Bertrand dot Lecun at prism dot uvsq dot Fr
17 years ago
It would be great to precise in the fscanf documentation
that one call to the function, reads a complete line.
and not just the number of values defined in the format.

If a text file contains 2 lines each containing 4 integer values,
reading the file with 8 fscanf($fd,"%d",$v) doesnt run !
You have to make 2
fscanf($fd,"%d %d %d %d",$v1,$v2,$v3,$v4);

Then 1 fscanf per line.
up
2
eugene at pro-access dot com
22 years ago
If you want to read text files in csv format or the like(no matter what character the fields are separated with), you should use fgetcsv() instead. When a text for a field is blank, fscanf() may skip it and fill it with the next text, whereas fgetcsv() correctly regards it as a blank field.
up
1
worldwideroach at hotmail dot com
19 years ago
Yet another function to read a file and return a record/string by a delimiter. It is very much like fgets() with the delimiter being an additional parameter. Works great across multiple lines.

function fgetd(&$rFile, $sDelim, $iBuffer=1024) {
$sRecord = '';
while(!feof($rFile)) {
$iPos = strpos($sRecord, $sDelim);
if ($iPos === false) {
$sRecord .= fread($rFile, $iBuffer);
} else {
fseek($rFile, 0-strlen($sRecord)+$iPos+strlen($sDelim), SEEK_CUR);
return substr($sRecord, 0, $iPos);
}
}
return false;
}
up
-1
nico at nicoswd dot com
11 years ago
If you want to parse a cron file, you may use this pattern:

<?php

while ($cron = fscanf($fp, "%s %s %s %s %s %[^\n]s"))
{

}

?>
up
-2
loco.xxx at gmail dot com
18 years ago
to include all type of visible chars you should try:

<?php fscanf($file_handler,"%[ -~]"); ?>
up
-3
robert at NOSPAM dot NOSPAM
22 years ago
actually, instead of trying to think of every character that might be in your file, excluding the delimiter would be much easier.

for example, if your delimiter was a comma use:

%[^,]

instead of:

%[a-zA-Z0-9.| ... ]

Just make sure to use %[^,\n] on your last entry so you don't include the newline.
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