---
name: "strict_strtoull"
section: "9"
platform: "linux"
package: "linux-manual-2.6.32"
version: "2.6.32-48squeeze6"
release: "Debian 6.0 (Squeeze)"
platforms: ["linux"]
url: "https://new.carta.tech/strict_strtoull"
---

# strict\_strtoull(9)

convert a string to an unsigned long long strictly

## NAME

strict\_strtoull - convert a string to an unsigned long long strictly

## SYNOPSIS

**int strict\_strtoull(const char \*** *cp***, unsigned int** *base***, unsigned long long \*** *res***);**

## ARGUMENTS

*cp*

The string to be converted

*base*

The number base to use

*res*

The converted result value

## DESCRIPTION

strict\_strtoull converts a string to an unsigned long long only if the string is really an unsigned long long string, any string containing any invalid char at the tail will be rejected and -EINVAL is returned, only a newline char at the tail is acceptible because people generally

## CHANGE A MODULE PARAMETER IN THE FOLLOWING WAY

echo 1024 \> /sys/module/e1000/parameters/copybreak

echo will append a newline to the tail of the string.

It returns 0 if conversion is successful and \*res is set to the converted value, otherwise it returns -EINVAL and \*res is set to 0.

simple\_strtoull just ignores the successive invalid characters and return the converted value of prefix part of the string.

## COPYRIGHT