curl_getenv.3 2.1 KB

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  24. .TH curl_getenv 3 "30 April 2004" "libcurl 7.12" "libcurl Manual"
  25. .SH NAME
  26. curl_getenv - return value for environment name
  27. .SH SYNOPSIS
  28. .nf
  29. #include <curl/curl.h>
  30. char *curl_getenv(const char *name);
  31. .fi
  32. .SH DESCRIPTION
  33. curl_getenv() is a portable wrapper for the getenv() function, meant to
  34. emulate its behavior and provide an identical interface for all operating
  35. systems libcurl builds on (including win32).
  36. You must \fIcurl_free(3)\fP the returned string when you are done with it.
  37. .SH EXAMPLE
  38. .nf
  39. char *width = curl_getenv("COLUMNS");
  40. if(width) {
  41. /* it was set! */
  42. curl_free(width);
  43. }
  44. .fi
  45. .SH AVAILABILITY
  46. Always
  47. .SH RETURN VALUE
  48. A pointer to a null-terminated string or NULL if it failed to find the
  49. specified name.
  50. .SH NOTE
  51. Under unix operating systems, there is no point in returning an allocated
  52. memory, although other systems will not work properly if this is not done. The
  53. unix implementation thus has to suffer slightly from the drawbacks of other
  54. systems.
  55. .SH "SEE ALSO"
  56. .BR getenv "(3C), "