curl/docs/libcurl/curl_getenv.3

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.TH curl_getenv 3 "30 April 2004" "libcurl" "libcurl"
.SH NAME
curl_getenv - return value for environment name
.SH SYNOPSIS
.nf
#include <curl/curl.h>

char *curl_getenv(const char *name);
.fi
.SH DESCRIPTION
curl_getenv() is a portable wrapper for the getenv() function, meant to
emulate its behavior and provide an identical interface for all operating
systems libcurl builds on (including win32).

You must \fIcurl_free(3)\fP the returned string when you are done with it.
.SH EXAMPLE
.nf
int main(void)
{
  char *width = curl_getenv("COLUMNS");
  if(width) {
    /* it was set! */
    curl_free(width);
  }
}
.fi
.SH AVAILABILITY
Always
.SH RETURN VALUE
A pointer to a null-terminated string or NULL if it failed to find the
specified name.
.SH NOTE
Under unix operating systems, there is no point in returning an allocated
memory, although other systems does not work properly if this is not done. The
unix implementation thus suffers slightly from the drawbacks of other systems.
.SH "SEE ALSO"
.BR getenv (3C)