curl/docs/libcurl/curl_easy_unescape.md
Daniel Stenberg e3fe020089
docs/libcurl: generate PROTOCOLS from meta-data
Remove the PROTOCOLS section from the source files completely and
instead generate them based on the header data in the curldown files.

It also generates TLS backend information for options marked for TLS as
protocol.

Closes #13175
2024-03-23 18:13:03 +01:00

76 lines
1.9 KiB
Markdown

---
c: Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al.
SPDX-License-Identifier: curl
Title: curl_easy_unescape
Section: 3
Source: libcurl
See-also:
- curl_easy_escape (3)
- curl_free (3)
Protocol:
- All
---
# NAME
curl_easy_unescape - URL decodes the given string
# SYNOPSIS
~~~c
#include <curl/curl.h>
char *curl_easy_unescape(CURL *curl, const char *input,
int inlength, int *outlength);
~~~
# DESCRIPTION
This function converts the URL encoded string **input** to a "plain string"
and returns that in an allocated memory area. All input characters that are URL
encoded (%XX where XX is a two-digit hexadecimal number) are converted to their
binary versions.
If the **length** argument is set to 0 (zero), curl_easy_unescape(3)
uses strlen() on **input** to find out the size.
If **outlength** is non-NULL, the function writes the length of the returned
string in the integer it points to. This allows proper handling even for
strings containing %00. Since this is a pointer to an *int* type, it can
only return a value up to *INT_MAX* so no longer string can be returned in
this parameter.
Since 7.82.0, the **curl** parameter is ignored. Prior to that there was
per-handle character conversion support for some old operating systems such as
TPF, but it was otherwise ignored.
You must curl_free(3) the returned string when you are done with it.
# EXAMPLE
~~~c
int main(void)
{
CURL *curl = curl_easy_init();
if(curl) {
int decodelen;
char *decoded = curl_easy_unescape(curl, "%63%75%72%6c", 12, &decodelen);
if(decoded) {
/* do not assume printf() works on the decoded data! */
printf("Decoded: ");
/* ... */
curl_free(decoded);
}
curl_easy_cleanup(curl);
}
}
~~~
# AVAILABILITY
Added in 7.15.4 and replaces the old curl_unescape(3) function.
# RETURN VALUE
A pointer to a null-terminated string or NULL if it failed.